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Best Backpacking Water Filter of 2020

Eddie enjoys cold water high in the alpine environment of the San Juan mountains. He uses one of the many Sawyer Squeeze products that we love.
Tuesday October 6, 2020
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Our experts have tested over 70 of the best backpacking filters of the last decade. This 2020 update features 24 of the market's current and best for use in the backcountry. We have spent years trundling through dense forests, climbing to the tops of mountains, exploring the far reaches of the Northern Hemisphere, and sampling water sources for all around. We have filtered thousands of liters of water from pristine lakes to polluted puddles and rivers across the world in the process of testing these products. After testing each product, hands-on, and comparing performance, we offer your recommendations to purify and filter water effectively while exploring the great outdoors.

Top 24 Product Ratings

Displaying 6 - 10 of 24

Best Overall for Group Use


Platypus GravityWorks


76
OVERALL
SCORE
  • Water Quality - 20% 8
  • Durability & Maintenance - 20% 6
  • Treatment Time - 15% 9
  • Weight & Packability - 15% 7
  • Ease of Set-Up - 15% 7
  • Ease of Filtration - 15% 9
Effective against: Particulates, Bacteria, Protozoa | Weight: 11.5 oz
Speedy treatment time
Easy use
Relatively lightweight
Can treat and store up to 8L
Hard to close
Hard to collect water from some sources
Questionable hanging attachments

The Platypus GravityWorks is our favorite gravity backpacking water filter that quite literally does it all. Its fast and portable nature makes setup easy to use for personal use or a small group. It features two durable bags marked as "clean" and "dirty" in addition to a high-flow filter that is compatible with water bottles and hydration bladders. The bags can easily be converted into a solar shower or handwashing station to make your base camp complete. We love that we can simply hang it up, walk away, and enjoy pump-free filtered water whenever we get into the backcountry.

Unfortunately, this system does not treat viruses, and the bags can be hard to close in cold weather. The attachments used to hang the bag look less durable than other options. Also, like any gravity filter that uses an in-line filter, it'll slow down if exposed to water with high amounts of sediment. That said, if you're seeking a stellar gravity filter, this is our recommendation for its durable architecture and high rate of flow.

Read Review: Platypus GravityWorks

Best Overall for Personal Use


Sawyer Squeeze


Editors' Choice Award

$29.97
(19% off)
at Amazon
See It

73
OVERALL
SCORE
  • Water Quality - 20% 8
  • Durability & Maintenance - 20% 5
  • Treatment Time - 15% 9
  • Weight & Packability - 15% 7
  • Ease of Set-Up - 15% 7
  • Ease of Filtration - 15% 8
Effective against: Particulates, Bacteria, Protozoa | Weight: 5.7 oz
Fast Flow
Versatile & adaptable
Packable & lightweight
Great price
Squeeze bags are the weak point
Parts are easy to lose
Not for groups

The Sawyer Squeeze is one of the most time-tested on-the-go filtration systems. This lightweight backpacking water filter is a wonderful option for personal use, providing great functionality on multi-day excursions and daily adventures into the backcountry. Of the multiple Sawyer Squeeze systems, this offers the fastest flow rate, filtering one liter of water in just 40 seconds in our tests. It's also packable, easily fitting into a running pack or pocket. Use it as a squeeze-filter with its accompanying bags or in-line with a hydration bladder. You can even screw it to the top of a compatible water bottle and drink directly from puddles with its complementary straw. Few contenders offer this level of versatility and portability, making it our favorite for personal use.

In our three years of experience, the provided filtration bags have typically broken after just three to four trips, at which point they require replacement. When we use it, we use it with a Platypus Hydration Bladder, as this burly bag doesn't break when squeezed repeatedly in our experience. It also comes with small parts, which are super easy to lose. If you're heading out on a big adventure, buy a compatible and stronger bag if you plan to use this versatile and lightweight filter for long trips.

Read Review: Sawyer Squeeze

Best Bang for Your Buck


Katadyn Gravity Camp 6L


Best Buy Award

$77.20
(14% off)
at Amazon
See It

74
OVERALL
SCORE
  • Water Quality - 20% 8
  • Durability & Maintenance - 20% 7
  • Treatment Time - 15% 8
  • Weight & Packability - 15% 6
  • Ease of Set-Up - 15% 6
  • Ease of Filtration - 15% 9
Effective against: Particulates, Bacteria, Protozoa | Weight: 11.7 oz
Lightweight & packable
High-speed flow rate
Treats up to 6 liters of water quickly
Inexpensive
Easy setup & durable design
Does not come with a storage bag
Clogs quickly with turbid water

We love the Katadyn GravityWorks for its easy to use design and fast flow rate. It treats vast quantities of water in minutes, making it an excellent option for a large group or solo use. Filling is easy. The bag has a large opening and can easily be used to collect large amounts of water from rivers, lakes, and streams. Gravity will pull water through the filter as you set up camp or cook dinner, provided you have a high point to suspend it from. It's also compatible with most hydration bladder systems and can double as a handwash station or shower. We especially like the bag's fabric design that seems quite durable, increasing its value in our eyes.

Unlike other gravity filters in this review, it does not come with an additional storage bag for clean water. Also, the placement of the filter adds limitations. The first is reduced functionality if there are no branches to hang it from. The second is that if a water source is turbid, it will clog, as it did in our experience. The third is difficulty cleaning; the filter is harder to backwash and clean based on its in bag placement. To prevent this, we recommend cleaning the filter as often as possible. Overall, we like the size of the bag and its versatility. If you're willing to work a little harder to manage it in dirty water, the lower price is definitely worth your while.

Read Review: Katadyn Gravity Camp 6L

Best Collapsible Bottle Filter


Katadyn BeFree


Top Pick Award

$38.76
(3% off)
at Amazon
See It

75
OVERALL
SCORE
  • Water Quality - 20% 8
  • Durability & Maintenance - 20% 1
  • Treatment Time - 15% 10
  • Weight & Packability - 15% 10
  • Ease of Set-Up - 15% 9
  • Ease of Filtration - 15% 9
Effective against: Particulates, bacteria, and protozoa | Weight: 2.1 oz
Lightweight & collapsible bottle
Adaptable filter
Fast flow rate
Easy maintenance
Small treatment capacity
Not very durable

Are you going out for a long day in the hills? The Katadyn BeFree is a personal soft hand bottle that fits a high flow filter with a short length inside. Scoop water on-the-go and drink straight from it. It'll filter as you drink, fueled by a soft squeeze and your sucking force. The soft bottle top is adaptable to other narrow bottle tops, making it reusable if your bag happens to spring a leak. In the field, the short filter and collapsible bottle rolls up to the size of your palm and is easily packable.

The biggest issue with this product is the durability of the soft bottle. We have had this bottle spring leaks on us pretty consistently over the last five testing periods. So it's not durable. However, since it is adaptable to other bottles, it can be used over and over again. It also only holds 0.6 L of water and can't be used for large storage, so water sources need to be plentiful. Use this system if you're seeking a super lightweight filtration option that boasts a high flow rate and a soft collapsible bottle that's packable.

Read Review: Katadyn BeFree

Best Chemical Treatment


Aquamira Water Treatment Drops


72
OVERALL
SCORE
  • Water Quality - 20% 5
  • Durability & Maintenance - 20% 10
  • Treatment Time - 15% 2
  • Weight & Packability - 15% 9
  • Ease of Set-Up - 15% 8
  • Ease of Filtration - 15% 9
Effective against: Bacteria, protozoa, and viruses | Weight: 3.0 oz
Lightweight and extremely packable
Effective on all microorganisms
Can treat all quantities of water
Long incubation time to eliminate cryptosporidium cysts
Doesn't remove particulates
Chemical taste
High price per liter purified

If you've got time to wait for your potable water, the Aquamira Water Treatment Drops is a lightweight and inexpensive travel system used by many thru-hikers. Treatment is simple: activate the substances, then drop it into your water and wait. Of all the chemical treatment systems, it kills the most stuff, including finicky cryptosporidium cysts. When doubled with a filtration system, it can easily be used anywhere in the world.

Unfortunately, chemical treatment doesn't filter out particulates, so we'd recommend carrying a pre-filter or a handkerchief to do that work. While it's advertised that treatment time is just 15 minutes, which will kill most stuff, you have to wait much longer (four hours is recommended) to get rid of hard-shelled cryptosporidium cysts, a protozoan found in North America. These drops are our favorite chemical treatment for backcountry water.

Read Review: Aquamira Water Treatment Drops

Best UV Bottle Purification System


CrazyCap 17oz


Top Pick Award

$69.95
at Amazon
See It

68
OVERALL
SCORE
  • Water Quality - 20% 5
  • Durability & Maintenance - 20% 7
  • Treatment Time - 15% 5
  • Weight & Packability - 15% 5
  • Ease of Set-Up - 15% 9
  • Ease of Filtration - 15% 10
Effective against: Viruses, bacteria, protozoa | Weight: 12.6 oz
Extremely easy water purification
Fast charging speed & long charge
Insulated water bottle maintains temperatures
Durable and waterproof
Can't filter out particulates
Doesn't protect from chemicals, heavy metals, or pesticides

The CrazyCap uses a UV light to sterilize surfaces from viruses, bacteria, and protozoa. It uses a USB charge cable to charge up this bottle cap (that is compatible with some other bottles), so maintenance is easy. Simply press on the top twice to purify the water you've collected in the bottle, and get 0.5 liters in just 60 seconds. The cap based system makes it versatile, and it can easily be used while hiking, traveling abroad, or around the house. The UV cap can even be used to sterilize surfaces around the house for potential viruses and other infectious agents, which some might consider a huge advantage.

While this system is quite nice, we've got to say it's hard to trust that a UV light is actually working to destroy viruses. It almost seems magical and takes some trust. Aside from that, this is not a filtration system, so don't expect it to get rid of particulates in the water. It also doesn't protect from chemicals, pesticides, or heavy metals, so don't go scooping up water where these could be present. This self-contained UV light water purifier is super convenient and an option we'd recommend to consider for international travel.

Read Review: CrazyCap 17oz

Excellent for Turbid Water


MSR Guardian Purifier


72
OVERALL
SCORE
  • Water Quality - 20% 9
  • Durability & Maintenance - 20% 9
  • Treatment Time - 15% 8
  • Weight & Packability - 15% 2
  • Ease of Set-Up - 15% 8
  • Ease of Filtration - 15% 6
Effective against: Viruses, particulates, bacteria, protozoa | Weight: 1 lb 4.5 oz
Collect water from almost any water source
Incredibly durable
Fast & easy flow
Amazing backflushing that requires no maintenance
Super long filter life
Heavy
Big investment

The MSR Guardian stands out for its exceptional ability to purify water of water-borne viruses, unlike other hand pumps on the market. The hollow fiber filter has a massive expected lifespan (which presents a great value), and there's no need for maintenance. It's built to last, it's tough, it's strong. We've owned one for over six years, and it's done great work for us traveling in international countries and hiking in the backcountry. Its flow rate is exceptional for a pump filter (about 37 seconds for one liter), while the backflush system makes it functional even in the sludgiest of stagnant or turbid water holes. The filter is resilient to freezing, making it an option to consider for trips in colder climates. It's also the only system that actually performed remarkably well in turbid water. If you encounter water muddied with sediment, this is the one we reach for.

While this purification system is quite incredible, it's not for everybody. The initial price tag is immense and quite frankly, most people aren't willing to pay. If you're looking for a pump filter that'll do work here in North America, you probably don't need this Cadillac of hand pumps; a normal hand pump will do. This model is rather large, which takes up space and adds to the pack weight more than others. But, if you need a purifier for international travel or one that sports a backflush system in muddied water, this is one worth investing in.

Read Review: MSR Guardian Purifier

Large Capacity for Groups or Basecamps


MSR AutoFlow XL


63
OVERALL
SCORE
  • Water Quality - 20% 8
  • Durability & Maintenance - 20% 6
  • Treatment Time - 15% 4
  • Weight & Packability - 15% 4
  • Ease of Set-Up - 15% 6
  • Ease of Filtration - 15% 9
Effective against: Particulates, bacteria, and protozoa | Weight: 16.2 oz
Easy set-up
Large volume reservoir
Lightweight & Packable
Sediment catcher
Slower flow rate
Requires regular maintenance

The MSR Autoflow XL is a gravity backpacking water filter designed for large group use and basecamps. Its large capacity can hold up to 10L of water, with an adaptable design fitting many different storage vessels. This is our favorite for group use because it requires minimal setup and can be left unattended while filtering large quantities of water. It also doubles as a handwash station or even a shower during the warmer seasons.

While we do love this system, it offers the slowest flow of any gravity filter tested. The filter needs consistent backflushes, especially when dealing with turbid water. As long as users know and accept this fact, it's a fantastic large group option. The filter can process 22 lbs of water. If you need to use its whole capacity, site selection can be limited by the availability of strong anchors to hang this model from.

Read Review: MSR Autoflow XL

Top Value Hand Pump


Katadyn Hiker


63
OVERALL
SCORE
  • Water Quality - 20% 8
  • Durability & Maintenance - 20% 6
  • Treatment Time - 15% 7
  • Weight & Packability - 15% 5
  • Ease of Set-Up - 15% 7
  • Ease of Filtration - 15% 4
Effective against: Particulates, Bacteria, Protozoa | Weight: 15.2 oz
Water pumping is easy and relatively fast
The filter can be rinsed out and cleaned
Reliable construction
Good price
Need to replace the filter if it gets completely clogged
Not the most robust hand pump
Tubes can be a pain to attach and reattach
The filter can't be frozen

The Katadyn Hiker is a reliable pump filter that's one of the best selling on the market. The pump-action system collects water while you actively pump it through the device into your water bottle. It works best with a wide-mouthed container (i.e., Nalgene bottle) and also has a hydration bladder compatible attachment so you can fill up hydration bladders with ease. This mid-range pump is fast, smooth, and easy to use. It's one of the most consistent in its performance, offered at a great price.

Unfortunately, if this thing clogs up completely, you can unscrew the housing and attempt to clean it out. Still, the manufacturer advises a full replacement of the cartridge if this occurs. The filter absorbs water and cannot be subject to freezing. If the filter freezes, it will no longer be effective. If you're looking for a hand pump, this one is most likely to get the job done and save you significant cash.

Read Review: Katadyn Hiker

Best Bottle Press Purifier


Grayl Geopress


72
OVERALL
SCORE
  • Water Quality - 20% 10
  • Durability & Maintenance - 20% 5
  • Treatment Time - 15% 9
  • Weight & Packability - 15% 2
  • Ease of Set-Up - 15% 9
  • Ease of Filtration - 15% 8
Effective against: Particulates, Bacteria, Protozoa, Viruses, Chemicals, Heavy Metals | Weight: 19.4 oz
The best water quality
Easy use
Easy maintenance
Super bulky design
Purifies only small amounts of water at once
Short comparative cartridge life

The Grayl Geopress quickly turned into one of our most used and favorite purification systems. In comparison to the rest, it supersedes most systems for a variety of reasons. It's easy to collect water, push it through the system, and drink. More importantly, this water purifier removes the most disgusting water contaminants that you would find. Not only including viruses, but it's said to remove heavy metals, plastics, pesticides, and more. When we tested this in a heavy metal polluted river in Ouray, CO, our water came out clear. No other system could purify as well. The bottle is pretty durable, and you can get a mouthful of water in seconds. Save yourself from buying tons of water bottles when you travel and get this instead. You can gather water from nearly any polluted source and trust in its water quality.

In comparison to the Grayl Ultralight system, this bottle is much easier to push down, especially with the handgrips along the side. While we appreciate the use of this system, it's also not our first choice for lightweight travel in the backcountry. While some users do use it as a bottle for backpacking, its heavy and bulky design is a bit much, and it doesn't filter large quantities of water quickly. The cartridge life is minimal, and the refills are pretty expensive. Based on these cons and our comparisons, we find this product provides relatively low value for the price. But for traveling, especially in urban areas abroad, we think the Geopress offers peace of mind.

Read Review: Grayl Geopress


Using the Sawyer Micro during a ski adventure to find sweet descents towards the end of August. While snow is typically scarce this time of year  we appreciate the lightweight nature of this on-the-go filter to support our ambitions.
Using the Sawyer Micro during a ski adventure to find sweet descents towards the end of August. While snow is typically scarce this time of year, we appreciate the lightweight nature of this on-the-go filter to support our ambitions.

Why You Should Trust Us


Jessica Haist and Amber King are seasoned gear testers (over 15 years of collective experience) that love to explore in the backcountry. Both work in outdoor education. As educators, they spend lots of time in the woods, backpacking along trails and exploring remote locations. You can find Jessica playing at the local granite crags, sucking up rays of the sun, or riding trails on her mountain bike. Amber is an avid ultrarunner and rock climber. She currently runs and owns a non-profit that takes kids into the backcountry daily. Also, she loves to fastpacking and backpack through remote and high mountains regularly. Both use backpacking water filters for work and recreation regularly.

We ran, hiked, and biked hundreds of remote trail miles in our testing, glugging gallons of water filtered and purified from some questionable sources. We test each product through an unbiased lens. We assess each system's anatomy, dissect the pros and cons, and evaluate whether or not a system is reliable enough to earn our favor. Each product sees both hands-on, in-field experience, with at least a week or more on the trail. We also perform rigorous indoor tests to determine minute differences between products. Our recommendations come from experience in the field and home-based experiments that comparatively test each product's performance.

The Flex is easy to assemble  just fill the bottle and screw on the filter!
The Katadyn Gravity filter adapts easily to a hydration bladder to filter out super silty water from the Colorado River. (Note: the yellowish color is because there was iodine in that bladder previous to this)

Related: How We Tested Backpacking Water Treatments

Analysis and Test Results


This review features a wide range of water filters and purification systems. We explore options from simple tablets to complex purification systems. Each system in this review is designed for backcountry use. To rate each product, we test them across six important metrics, including; water quality, maintenance, treatment time, portability, ease of setup, and ease of filtration. While some products are like comparing apples to oranges, we use this rating to help you find a product that best jives with your hydration needs, depending on where you travel.

Related: Buying Advice for Backpacking Water Treatments


Value


A great purifier or filter is one that lasts a long time and doesn't cost an arm and a leg to maintain. While the original ticket price on some items might seem really low, the expenses of replacement pieces might add up, running up a larger bill in the long run. To take a critical look at value, we took the time to calculate the cost per 100L of water for each filtration system. We also look at the price per 100 liters for the refillable filter cartridge. By looking at this data, you can see which systems offer the best upfront and long-term value. Of all these systems, the Sawyer Squeeze systems and the CrazyCap offer excellent value. Both offer more filtered or purified liters before needing replacement than other models we tested.


The Katadyn Gravity Camp is a gravity filter that provides a great option for larger groups at a lower upfront cost and a reduced maintenance fee. The Katadyn Hiker Microfilter is a pump filter with a low upfront cost and great reliability and longevity for the single hiker. Both models are affordable and have different needs in mind. While purification tablets and liquids like the Potable Aqua Drinking Water Germicidal Tablets and Aquamira Water Treatment Drops have a super low upfront cost, they actually offer a lesser value per liter as they need to be replaced every 30 liters or so. When considering the price, consider how you'd like to pay for your system — either with small, repetitive costs, or a larger sum but much less frequently.

We've been impressed for many years by the value that Sawyer products present  like the one shown here filling from a mountain stream.
We've been impressed for many years by the value that Sawyer products present, like the one shown here filling from a mountain stream.

Water Quality


When considering this metric, we specifically look at what the backpacking filters can get rid of and the overall taste or odor of the water. We went to shallow puddles, smelly swamps, and pristine streams to see what each could do. Those that remove everything, including heavy metals and pesticides, triumphed in this category.


Backpacking water filters and purifiers use different types of technology to remove viruses in addition to protists, bacteria, and other water-borne pathogens. Filters typically don't have a pore size that can remove viruses. Other categories are chemical tablets and UV light systems. Below, we outline the different types of purifiers and filters out there and what they can eliminate.

The Grayl Geopress (left) does the best in our water quality tests. All other filters processed this soil sludge filled with pesticides and other chemicals and produced this yellow colored water (right). While the Geopress produced clear  clean water that we actually trusted to drink.
The Grayl Geopress (left) does the best in our water quality tests. All other filters processed this soil sludge filled with pesticides and other chemicals and produced this yellow colored water (right). While the Geopress produced clear, clean water that we actually trusted to drink.

Water Purifiers

Water purifiers are what you need if you're traveling abroad or treading in terribly polluted areas. Water purifiers remove particulates, protists, and bacteria, but can also rid the water of viruses. For example, the MSR Guardian is a tried and tested hand pump purifier that can do just that. It can expunge smells from water and remove viruses, but it can't remove heavy metals or chemicals from water sources. That said, if you're traveling internationally, it's a great companion to pump water from the sink or collect from a local stream.

A look at the purified product  provided by one of our favorite purification systems. It is said to offer protection from heavy metals  particulates  viruses  and other living organisms. In our tests  it was the only one that would remove the yellow color of this polluted river.
A look at the purified product, provided by one of our favorite purification systems. It is said to offer protection from heavy metals, particulates, viruses, and other living organisms. In our tests, it was the only one that would remove the yellow color of this polluted river.

The Grayl Geopress stands out above the rest because this water bottle purification system uses push technology to scrub water of everything that might contaminate it. We tried this on a particularly contaminated stream in Ouray, Colorado, that runs yellow from pollutants like lead, arsenic, chromium, and iron oxides. The water smells acidic, and is acidic. After using the purifier, it took all these metals out and neutralized the pH of the water, which amazed our testers. We drank it shortly after, not noting any weird tastes or side-effects. The Grayl Ultralight provides the same level of water quality as well but is much more of a pain to use. This is a filter we'd trust taking water from any source, whether you're traveling to Africa, Thailand, India, or anywhere abroad. We'd also take the MSR Guardian with us, but we'd be more careful about where we get our water from. That said, the MSR Guardian has a much longer lifespan and can process more water in bulk, where the Grayl can only process 750mL at a time.

The Aquamira Frontier Max is a unique in-line purification system that removes viruses and other contaminates. It can be attached to a hydration bladder hose, gravity filter, or used on its own to provide water purification. So instead of filtering your water and drinking it, you suck it through the filter. It also has the ability to remove all the substances that you can think of. A good option if you don't like to pump or press water. The only issue is it takes quite a bit of sucking power.

The Guardian Purifier is at home anywhere in the world. Here we use it in the pristine alpine meadows in the Sierra Nevada. While this technology is a little overkill for this environment  it's a great option for travel abroad in developing nations.
The Guardian Purifier is at home anywhere in the world. Here we use it in the pristine alpine meadows in the Sierra Nevada. While this technology is a little overkill for this environment, it's a great option for travel abroad in developing nations.

UV Light

UV light purifiers also effectively eliminate water pathogens. Imagine sitting on a beach in Mexico with a tequila-infused beverage with ice. Unsuspectingly, you get sick. Why? Ice is typically a huge source of sickness for travelers as it carries bacteria. UV light like the SteriPEN Ultra, a UV purifier can be put into the glass and swirled around to destroy pathogens that could cause an infection. We tested two UV purifiers in this review, the SteriPen and CrazyCap. Both are easy to use. The SteriPen is a long structure that you swish around in your water while the CrazyCap is a lid with a UV light built into the bottom, so purification happens inside the bottle. Both offer the same water quality level. Unfortunately, UV light purifiers won't remove particulates, smells, or metals and don't score as high as other purification models because of this.

The SteriPEN Ultra uses ultraviolet light to get rid of harmful microorganisms.
The SteriPEN Ultra uses ultraviolet light to get rid of harmful microorganisms.

Chemical Treatment

The Aquamira Water Treatment Drops is our favorite chemical treatment. It can kill most microorganisms but does impart an off-flavor to the water. In addition, they can't filter out particulates. The Aquamira drops are the best because they kill all organisms (with enough time) while the Potable Aqua Iodine Tablets and MSR Aquatabs can only destroy viruses, bacteria, and some protozoans, but not Cryptosporidium. The active ingredients in these treatments cannot get rid of Cryptosporidium as the drops do. The drops have the least "chemical" taste of all three options, which scored by points among our testers.

Pouring the Aquamira drops into our water to kill anything that we'd be concerned about.
Pouring the Aquamira drops into our water to kill anything that we'd be concerned about.

Water Filtration Units

A backpacking water filter (not purifiers) can remove particulates, bacteria, protozoans (Giardia & Cryptosporidium) but cannot remove viruses. The best filtration systems can remove chemicals, heavy metals, and odors using activated carbon embedded in the core of the media.

The Platypus GravityWorks hard at work  cleaning out super turbid water and turning it into delicious and drinkable water.
The Platypus GravityWorks hard at work, cleaning out super turbid water and turning it into delicious and drinkable water.

Of the backpacking water filters, the Katadyn Hiker Pro, Katadyn Hiker Microfilter, MSR Miniworks EX, and Lifestraw Universal offer protection from both microorganisms and chemicals like pesticides to improve the taste of the water. The LifeStraw Flex can remove lead, which is a unique property. This is an excellent option if you are concerned about lead in your water sources.

Filters that utilize a hollow fiber filtration media, like the Platypus GravityWorks and the MSR Autoflow XL, are plentiful in this review. If it doesn't have a carbon core, don't expect it to improve the taste of water or remove chemicals. These two gravity filters, for example, cannot remove these contaminants.

Filters remove particulates based on size. Bacteria are larger than protozoans, and viruses are about 10X smaller than bacteria. Cysts that come from Giardia and Cryptosporidium need a filter media smaller than 0.2-microns (a micron is 1 X 10^-6 meter). Purifiers that filter out based on size need a filter media with an absolute size of 0.02-microns (notice the extra zero) to filter out viruses. Dirt is much larger than all of these microorganisms.

A Note on Water Turbidity

It's essential to plan for water sources that might be saturated entirely with silty sediment (called highly turbid). For example, the Colorado River that has carved out popular backpacking locations like the Grand Canyon is one of the most turbid rivers in the world. If you live close to it, you've seen it transform from a clear greenish color to what looks like chocolate milk shortly after rainfall.

The highly turbid Colorado River is a place where you may want to pre-filter you water...even with the best filter out there.
The highly turbid Colorado River is a place where you may want to pre-filter you water...even with the best filter out there.

Most backpacking water filters and purification systems cannot deal with the amount of sediment and silt in water sources like this. The only system that held up in these conditions is the MSR Guardian Purification System, another reason it's one of our favorites. It utilizes an auto backflush that cleans the filter with every pump.

If you plan on traveling to areas with high turbidity, bring a gallon ziplock bag or a bag designated for settling water. Scoop up the silty water and let it settle for a few minutes. Clearwater will remain in the upper column, with sediment falling to the bottom. Gradually pour the upper layers of water into your filtration device, or filter from the top of the bag. This is an easy and cheap "pre-filtration" technique for these areas. Some gravity systems have a "sediment collecter" in the bottom, like the MSR Autoflow XL.

The space between the bottom of the bag and the intake provides a place for sediment to settle out. This is considered the "sediment trap" that works really well with turbid water.
The space between the bottom of the bag and the intake provides a place for sediment to settle out. This is considered the "sediment trap" that works really well with turbid water.

Durability and Maintenance


Reliable backpacking water filters are durable in construction. You don't want to be without a filter simply because it gets dropped. You also don't want to spend hours maintaining it. 21st-century products are available that offer high quality and reliable with minimal durability.


The most durable and reliable products are chemical treatments. Each comes in either jars or prepacked packets that can go into a plastic bag. They have no moving parts, don't require maintenance, and don't expire. If you want 100% reliability, this is it. The Aquamira Treatment Drops is a favorite of ours. We would strongly recommend carrying these as a backup system, especially when traveling into the backcountry for extended periods of time. There are too many situations where filters can clog, parts might be lost, or things may not work. Carrying these treatment drops can mean the difference between life, death, and grave discomfort.

Gravity Filters

Of this group, the Katadyn system seems to be one of the best constructed. The bag, unlike the Platypus and both the MSR systems, seems to be far more resistant to punctures and has a lot less going on. The Platypus is made of a strong plastic composite that could come apart at the seams, while the MSR is made of a more rubberized plastic compound. Of all these systems, they all seem very durable and reliable, with the Katadyn being the best.

This super-strong bag offers protection from punctures and breaks. The seams are welded  strong  and can hold the 22lbs of weight that this 10L reservoir is meant to hold.
This super-strong bag offers protection from punctures and breaks. The seams are welded, strong, and can hold the 22lbs of weight that this 10L reservoir is meant to hold.

All of these systems have filters that require frequent maintenance and care, depending on how much sediment is in the water you are filtering. Both the Platypus and MSR systems use the same hollow fiber technology. It's important to know that regular back flushes are required, which is simply flipping the filter upside down and allowing water to run through it. Alternatively, the Katadyn requires a rinse and has more moving parts, which is hard to clean with water that isn't clear of sediment in the first place. All systems are pretty durable and easy to use; just be sure that you're amenable to their maintenance to retain optimal flow.

Of the three, the Katadyn is the only one that can be used after it's been frozen. Given the filter's internal glass fiber construction, the filaments aren't destroyed when frozen. While it can't filter water when frozen, it is still usable after thawing out. If you're seeking a gravity filter that'll do for a winter camping trip, this is it. That said, it's not freeze-proof. That'd be an amazing innovation.

Hand Pumps

These models are pretty durable in general until they get clogged. The MSR Guardian is the most durable and maintenance-free backpacking water purification system that we'd trust anywhere. It auto cleans, even in turbid water, offering the best reliability in terms of hand pumps. It can also be frozen, unlike any other hand pump system. The MSR MiniWorks EX is another reliable hand pump. It uses a ceramic-carbon core that can easily be serviced in the field. Unfortunately, it does require a lot of maintenance to keep it working well (lots of scrubbing), but it can be fixed in the field.

A look at the ultra-reliable and easy to maintain MSR MiniWorks EX. While it doesn't win any awards  it is one of the easiest filters to service in the field.
A look at the ultra-reliable and easy to maintain MSR MiniWorks EX. While it doesn't win any awards, it is one of the easiest filters to service in the field.

The Katadyn Hiker Pro and Katadyn Hiker models are two of the best selling models on the market. Both are extremely consistent in performance. Both use a glass fiber filter that, if you allow it to become completely clogged, needs to be replaced. Both can be serviced infield, but you must be careful not to keep pumping if performance decreases. Between the two, the Hiker Pro is better by a hair. It's more durable and performs a bit better. For the minimal improvement, though, we tend to recommend the Hiker. These pump filters require less maintenance than the MSR MiniWorks EX.

The MSR Hyperflow is the fastest flowing pump filter tested, but also requires the most service. The filter, when clogged, can only be backflushed. To do that, you need to take the system apart completely. It requires regular backflushing (every 8L in clear water, more in turbid), and is a bit of pain. It's a durable unit but requires quite a bit of care.

The double tube is an auto backwash system that takes in water and cleans while pumping. Here we can see the threads that are compatible with Nalgenes and the bomber construction of the Guardian.
The double tube is an auto backwash system that takes in water and cleans while pumping. Here we can see the threads that are compatible with Nalgenes and the bomber construction of the Guardian.

Squeeze Systems

We are super impressed with the Sawyer Squeeze, lasting up to 10,000 gallons and pretty well built-in nature. Sawyer offers three systems, the regular Squeeze, Mini, and Micro. With all these systems, the bags breaking when in "squeeze" mode are the most annoying. When squeezed too hard, the bags break at the seams, with the Mini being the most problematic of them all. The regular Sawyer offers a good amount of flow, with less squeeze-force required, breaking fewer bags overall. All of these systems do require you to carry a plastic syringe to backflush after most uses. Overall, the regular Squeeze requires the least maintenance simply because it's a bigger squeeze system than the rest.

A look at the profile of the Sawyer Squeeze. However  make sure that you take extra bags with you on long trips since they aren't very durable.
A look at the profile of the Sawyer Squeeze. However, make sure that you take extra bags with you on long trips since they aren't very durable.

Another great squeeze bottle is the Katadyn BeFree 0.6L, our favorite for lightweight missions like trail running. The bottle that it comes with is also prone to leaking. However, we found that it can be attached to other hand bottle options that are much more durable. Overall, its durability is a drawback, but the filter itself offers some of the best flow and adaptability. Cleaning is easy; just swish it in clean water. You don't need to carry any extra parts, and clogging does not happen often.

The BeFree's hollow fiber filter unit is very small and light  and quite durable.
The BeFree's hollow fiber filter unit is very small and light, and quite durable.

On-the-Go Systems

The Sawyer Squeeze and Lifestraw Personal Water Filter are two options that we really like. If you're seeking the most barebones option that doesn't require you to carry extra items, the Lifestraw is where it's at. It's light, easy to carry, and long enough to provide easy access to water sources. Both the Squeeze Mini and Micro are fine options for on-the-go carry, but require you to carry a syringe and straw adaptor.

UV Light

This is one of the most unreliable systems simply because it needs a power source. Battery life can be tough to predict, especially in colder temperatures. The CrazyCap earns a higher score than the SteriPen here because it's completely waterproof. It also requires less time to charge overall. One charge lasted us about 30 liters but only took 1.5 hours to charge completely. After testing it for months, it was consistent. Neither are units we'd completely trust on a long backpacking trip, but both are suitable for travel or purifying municipal water sources on a regular basis.

The Crazy Cap is waterproof and offers excellent overall durability. It also requires next to no maintenance. It just needs to be charged.
The Crazy Cap is waterproof and offers excellent overall durability. It also requires next to no maintenance. It just needs to be charged.

Treatment Time


In this metric, we consider how quickly you can get water from the source to a filtered state. To test this, we noted if water filtration is instantaneous. If not, we performed three separate time trials and averaged them to determine an average time to filter one liter. The fastest times did best in this metric.


Straw Filters

The most immediate backpacking water filter systems are the straw filters that you can drink through immediately from a water source. The Aquamira Frontier Max and Lifestraw Flex are a few of our favorites. Water flow is typically slower but very much based on the construction of the input, filter body, and straw or bite value. For example, the Lifestraw Flex and Aquamira Frontier Max have comparable flow rates, not requiring as much effort as the laborious Lifestraw Personal Straw.

Little puddles in granite pockets are a perfect place to get water while alpine climbing with this model.
Little puddles in granite pockets are a perfect place to get water while alpine climbing with this model.

Squeeze Filters

These backpacking water filters use a collapsible bottle or pouch, offering a little water storage. The Sawyer products all demonstrate this adaptability, but our favorite is the Katadyn BeFree for its fast flow bite valve that delivers water quickly. This makes it a favorite among trail runners because water collection takes no time, and treatment is instantaneous.

Eddy works to clean water using the Sawyer filtration unit.
Eddy works to clean water using the Sawyer filtration unit.

Of all the Sawyer products, the Sawyer Squeeze offers the best flow rate. It can filter a liter of water in just 40 seconds when in squeeze mode. The Mini, the smallest of the group, takes 2 minutes to filter a liter of water, with the Micro somewhere in between. If you like the Squeeze products and want one with an awesome flow rate, the Sawyer Squeeze is the way to go.

Pump Filters

We pumped over 40L of water, timed it, just to see how many strokes each took, and which were the fastest. The hands-down winner in this category is the MSR Hyperflow (27 seconds, 29 strokes per liter). It pumps out hoards of water super quickly. However, this model was also the quickest to slow down, reducing its flow rate significantly as the liters added up. The MSR Guardian Purifier placed in second, filtering a liter in 37 seconds, and maintaining performance in even the murkiest of water. The other pumps followed as such — the Katadyn Hiker Microfilter (42 seconds, 52 strokes), then the Katadyn Hiker Pro (53 seconds per liter), and lastly, the MSR MiniWorks EX (80 seconds, 90 strokes per liter).

The MSR Hyperflow is the fastest pump filter tested  treating one liter of water in just under 30 seconds. Jack the dog and our main tester are impressed with its performance.
The MSR Hyperflow is the fastest pump filter tested, treating one liter of water in just under 30 seconds. Jack the dog and our main tester are impressed with its performance.

The Katadyn products and the MSR Guardian offered the most consistent performance overall, with these working best in Turbid conditions. The MSR Hyperflow and MiniWorks EX needed cleaning almost every 4L in these tests. In our sludge tests, all the pump filters needed to be cleaned out every liter, except the MSR Guardian.

Gravity Filters

Comparable in the flow rate, gravity filters are nice because you conveniently don't have to pump or do anything once they are set up. They can process large quantities of water, making them highly useful for small to large groups. All of the gravity filters are super close in treatment time.

The Gravity Camp by Katadyn is so fast there is virtually no wait time to fill a liter. Simply just fill and wait for water to fill your bottle easily.
The Gravity Camp by Katadyn is so fast there is virtually no wait time to fill a liter. Simply just fill and wait for water to fill your bottle easily.

The Platypus Gravity System is the fastest, filtering one liter in 52 seconds. The Katadyn Gravity Camp filters one liter in 64 seconds. The MSR Base Camp is close behind at 69 seconds. Lastly, the MSR AutoFlow XL took just around 2 minutes per liter, making it the slowest gravity filter tested. While gravity filters are inherently rad because there's so little work involved, there are some stark differences in performance. Please note that these flow rates will decrease with murkier or turbid water, and if the filters are not properly maintained. Also, note that if you aren't rushing, the difference in passively waiting one or two minutes for a liter of water to be filled often isn't a big deal.

Weight and Packability


Weight and packability are essential. If you're carrying less weight, long hikes can be more enjoyable. To assess this metric, we weigh each system and look at its relative profile. We tested them with hydration vests, backpacking backpacks, and regular packs. Generally, products that were lighter and easier to pack scored better than bulkier options.


Of all the treatments out there, chemical treatments are by far the lightest. If you're planning a long thru-hike or huge trail run, they're a great choice. Of the treatments, the MSR Aquatabs and Potable Aqua Drinking Water Germicidal Tablets can simply be put into a little baggy, without requiring you to carry the whole bottle. This helps to eliminate weight. The only downside is that both of these result in a chemical taste in the water (for most people). The Aquamira Treatment Drops can't be parsed out like the tablets, but some prefer them because they don't taste as bad as the tablet options.

The TrailShort (part of the Trail Base package) and Katadyn BeFree are both marketed for trail running  but the BeFree is much lighter and more compact than the TrailShot. The collapsible bottle is perfect for storage.
The TrailShort (part of the Trail Base package) and Katadyn BeFree are both marketed for trail running, but the BeFree is much lighter and more compact than the TrailShot. The collapsible bottle is perfect for storage.

The lightest filtration systems out there are on-the-go systems like the collapsable Katadyn BeFree and Lifestraw Personal Filter. The lightest purifying on-the-go filter system is the Aquamira Frontier Max. Of the gravity filters, the Platypus Gravityworks is the lightest and most packable (11.5 oz). If you prefer a hand pump system, the lightest systems are the MSR Hyperflow (10.6 oz) and the Katadyn Hiker Pro (13.2 oz).

The Sawyer Mini (and its included straw) next to the LifeStraw (top) for size comparison. The Mini is much lighter and more compact than the LifeStraw  and in our opinion  more versatile as well.
The Sawyer Mini (and its included straw) next to the LifeStraw (top) for size comparison. The Mini is much lighter and more compact than the LifeStraw, and in our opinion, more versatile as well.

Ease of Setup


We measured ease of setup based on how intuitive backpacking water filters are and how many steps each one requires to set up. We also consider how easy it is to access different water sources.


The easiest setups are the ones that require little thought and easy access. The best score models have no parts to carry around or steps to follow. On-the-go systems prove to be the easiest here. The basic Lifestraw is the best for this. Unlike other more complex on-the-go systems, this filter requires you to find a puddle or accessible water source and simply drink.

Simple and easy. Just add the MSR tablets to water!
Simple and easy. Just add the MSR tablets to water!

Purification Tablets are also pretty simple. Those like the MSR Aquatabs and Potable Aqua Drinking Water Germicidal Tablets require you to drop them in the water and wait. The Aquamira Water Treatment Drops are also pretty simple, but with a steeper learning curve. These require you to follow a series of specific steps where you have to mix two solutions and wait a specified time amount of time. The time frame depends on what contaminates you need to eliminate from the water.

Hand pumps are also relatively easy to set up and offer great access to all sorts of water sources. The Katadyn Hiker Pro, Katadyn Hiker Microfilter, and MSR MiniWorks EX are favorites because the intake can grab water from the smallest nooks and crannies. The MSR Guardian works well for this, but it has a larger particle screen that makes it harder to reach shallow sources. Pump filters excel at reaching water over steep banks, boat sides, or fast rivers when water access can be an issue.

The Katadyn Hiker allows you to take water easily from any source. Steep banks  shallow streams  babbling brooks. This is due to its weighted intake with a high quality prefilter.
The Katadyn Hiker allows you to take water easily from any source. Steep banks, shallow streams, babbling brooks. This is due to its weighted intake with a high quality prefilter.

Gravity filters require more effort to set up because you need a place to elevate them. The ideal scenario is to hang the filter from a branch. If that is not available, you may need to get creative in a pinch; a rock could work. They typically earn a lower score in this category. Reservoirs that are very flexible with large openings like those found in the Katadyn Gravity Filter can get water from most water sources. However, because you have to scoop up water, the source needs to have a sufficient pool to collect water. Shallow pools are harder to reach.

The 10L MSR Autoflow system is a perfect way to cater to large groups or basecamp.
The 10L MSR Autoflow system is a perfect way to cater to large groups or basecamp.

Ease of Filtration


In the ease of filtration metric, we look at the amount of effort required physically to get water through the backpacking water filtration system. While we don't score storage capacity, we note how much water each system is designed to store or not store.


UV Purifiers

Of all the categories, both the SteriPen Ultra and CrazyCap require the least amount of work. Simply fill up the bottle and turn the light on. The SteriPen requires a little less time to filter a liter in comparison to the CrazyCap. However, we appreciate that the CrazyCap is completely hands-free, and you can keep hiking while it purifies your water.

Touch the button and do nothing else. This is by far one of the easiest purifier systems we've ever used.
Touch the button and do nothing else. This is by far one of the easiest purifier systems we've ever used.

Gravity Filters

Gravity backpacking water filters are by far the best systems when it comes to ease of filtration. After set up, the filtration process is hands-free. All gravity filters in our review earn top points, all being easy to filter. These filtration systems can move lots of water quickly, making them a top choice for groups. One difference is the height requirement to filter. The Katadyn Gravity works needs full suspension and can't be put on the ground while the MSR BaseCamp, MSR Autoflow, and Platypus Gravityworks can be laid on a hill or over a rock and still filter water.

The Gravity Camp is a great choice for most backpacking campsites.
The Gravity Camp is a great choice for most backpacking campsites.

Some come with "clean water" vessels like the MSR Basecamp and Platypus Gravityworks while others like the Katadyn and MSR Autoflow have a simple hose running from the bag to a storage vessel of your choice. All prove to adapt nicely with a hydration bladder and can be filtered into a bottle if needed.

Hand Pumps

Hand pumps are a little harder to use as you need to pump to move water through the system physically. Hand filters vary by design and efficiency, which is dictated by output per pump. Of the hand pumps we tested, the MSR Hyperflow and MSR Guardian are the easiest to use. Both are highly efficient filters, which translates to less pumping and more water production. The Guardian has a large handle that's easy to grab, similar to the MSR MiniWorks EX. The MSR Hyperflow has a tinier system, but it's still pretty ergonomic. All hand pumps we tested have attachments that fit a Nalgene bottle best. The Katadyn Hiker models both have easy to use handles, but they aren't as ergonomic as the MSR products. These also require more pumping to get more water. The MSR MiniWorks EX took the most work per liter of all the hand pump filters.

We love the large handle that makes the MSR MiniWorksEX easier to pump  even though it's one of the harder pumps to use out there.
We love the large handle that makes the MSR MiniWorksEX easier to pump, even though it's one of the harder pumps to use out there.

On-the-go Filters

On-the-go backpacking water filtration systems are typically easy to set up but are propelled by either sucking or squeezing forces. Of the on-the-go systems, the Katadyn BeFree, Sawyer Squeeze, and Aquamira Frontier Max are the easiest to suck through when in straw style. Others are harder, like the Sawyer Mini, that gives you very little water for each suckle. We also love the Lifestraw Adaptor Kit that turns a personal water bottle into a filtration system.

Sadly we lost the straw and had to get REALLY close to our water source  but the Mini kept us healthy and happy...despite this high sediment and stagnant water source. Here we trust it while running 20-some miles.
Sadly we lost the straw and had to get REALLY close to our water source, but the Mini kept us healthy and happy...despite this high sediment and stagnant water source. Here we trust it while running 20-some miles.

These systems don't offer much when it comes to water storage; however, they are adaptable. For example, Sawyer products come with a storage pouch that you can use to store water. Though, if you don't trust these bags, you can find a hydration bladder, a suitably-sized collapsible bottle, or even a regular water bottle that is compatible to use instead. You can also simply carry a "dirty Nalgene bottle" and drink through the on-the-go filters through that. Be aware not to drink from this vessel without the filter, or you may feel the impacts later.

The Sawyer systems come with handy water storage pouches that allow you to grab water on the go  and store it for whatever distance you intend to travel.
The Sawyer systems come with handy water storage pouches that allow you to grab water on the go, and store it for whatever distance you intend to travel.

The Katadyn BeFree bottles have a few different sizes and are compatible with other soft bottles that offer better durability and flow. But for the most part, they are designed to be carried when water sources abound. You can also fill up a "dirty bladder" and carry it around with you, drinking on the go.

Water treatment is an important consideration  especially when you are taking from questionable and stagnant sources. Be sure to choose your water filter or purifier wisely.
Water treatment is an important consideration, especially when you are taking from questionable and stagnant sources. Be sure to choose your water filter or purifier wisely.

Conclusion


There are a lot of different backpacking water filter options out there. Ultimately, you need to figure out what you need for weight, packability, and water quality. Before you go anywhere, be sure to research the water sources and what kinds of pathogens you may contact. Consider carrying a chemical treatment as a backup; its lightweight makes it a perfect companion for any adventure. Cheers to clean water and many adventures ahead deep into the backcountry.

Amber King and Jessica Haist