How to Choose the Best Backpack

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Article By:
and Ian Nicholson

Last Updated:

The styles, shapes, and sizes of backpacks are virtually limitless, not to mention overwhelming. You can find a pack specific to just about every outdoor activity and in just about any capacity. So how do you narrow this impossibly broad field to the exact one that will suit you?

Backpacking Checklist
See our list of all the essential items you need for your backcountry trip in our Backpacking Checklist.

Our first tip: don't start with a pack and try to fit your gear into it. Start with the pile of gear that you need to carry, and select the appropriate model to carry that gear. So, if you will be traveling with skis, look for one with a ski carry. If you will be taking ice tools, make sure they can attach to the outside of your pack with ease. And if you plan to carry your pack on a long distance hike, make sure the weight, suspension, and capacity is suited to what you need to bring with you.

Most people dedicated to the outdoors own more than one pack, especially if they participate in different sports. Most commonly, people own 3 different capacities that cover a a full range of load carrying: a 60+ liter pack for multi-day trips in the backcountry, a 35-40 liter pack for most gear intensive in-a-day missions, and a 20 liter or less pack for half-day adventures, side hikes, or carrying on routes.

Our goal is to help you determine which model or models and what volumes are right for you and the activities you engage in.

Selecting, Fitting, and Loading a Backpacking Pack

The most common and versatile pack style is a backpacking pack. This style can be complicated to purchase because there are several factors to consider: capacity, fit, and weight being the most important. Here we discuss those factors, but be sure to read our full comparison review to see our favorite models.


The first important question to ask yourself is what capacity of pack you need. Sometimes this can be limited by factors such as it needs to fit in an overhead bin on a plane, which on US airlines is a standard size of 22" x 14" x 9." Or, as we prefer to think of it, it should be determined by how much gear you need to carry, which is why many people will require more than one volume pack for different occasions. Do you need overnight gear? This will automatically put you in the 35+ liter range.

A huge determiner for pack capacity is trip length. Are you buying a pack for a specific trip such as a thru-hike lasting several months, or a once-a-year weekend guided mountaineering trip? Or are you buying a daypack to take hiking with you on weekends and would like the versatility of being able to do occasional overnighters as well? If buying for a specific trip, it is easier to determine what length your trip will be, the necessary gear you will bring, and therefore what volume to select. If you are buying a pack for general use and you take trips of various lengths, we would suggest choosing either 2 different packs with different volumes or selecting a pack that is large enough for your long trips that can be stripped down and compressed for shorter trips.

Below are some very basic guidelines for coming up with an ideal capacity, though it varies wildly with personal preference, activity type, and hiking style.

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This is a general guideline to help hikers choose a pack capacity. This traditional scale is for those luxury campers who plan to bring comfort items or sports enthusiasts who will be carrying skiing or climbing gear along with overnight gear.

This traditional scale is aimed at new backpackers, people who consider themselves comfort or heavyweight backpackers (you know who you are: carrying a spice container, a poop shovel, and a Crazy Creek chair), people who will be carrying gear for other sports along with their overnight gear, or for parents hiking with kids and pets who need to carry gear for more than one person.

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This is a general guideline to help hikers who prefer to carry lighter packs choose a pack capacity. This scale is for experienced hikers who can do without unnecessary extras and place an emphasis on finding lightweight and space saving gear.

This more pared down scale is more relevant to experienced backpackers, those who value moving light and fast, and those who have eliminated unnecessary items from their kit. This is also closer to the most common range for people on long thru-hikes such as on the Appalachian Trail or the Pacific Crest Trail, though ultralight set-ups are becoming increasingly common. Ultralight hikers and fast packers can get away with much less weight and much smaller packs. This scale is designed more for those who have trimmed down from luxury camping and hover somewhere in between heavyweight and ultralight.

Properly Sizing & Fitting a Pack

Different from its carrying capacity, selecting the correct size is the single most important detail when it comes to choosing a pack. Correctly sizing a pack is vitally important to your comfort and the pack's function. If is is too large or too small, weight will not be evenly distributed and will put pressure on different parts of your body, making hiking and moving difficult and painful. Usually small daypacks come in only one size, eliminating the need to choose from sizes. When carrying small amounts of weight, the size of the pack is less crucial, but for backpacking or mountaineering you will want the correct size for long term comfort.

When selecting a size from a typical scale of small, medium, or large it is your torso length, not your height, that puts you in the correct range. Most manufacturers will provide a size range saying how many inches of torso length each size range covers. For example, a small may cover 16-19 inches, a medium would fit a torso length of 18-21 inches, and a large may best fit a torso of 20-23 inches. (This varies by manufacturer, so make sure you double check before you buy.)

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Some companies use specific proprietary tools to assist in pack fitting, while nice; measuring tape still works just fine.
Each manufacturer has its own unique method of measuring your torso and fitting a pack, which can be helpful if you go in person to a brick and mortar store and are assisted by a sales associate who has access to each brand's specific chart or measuring device.

If you cannot make it to a store or you are shopping online, there is a standard way of measuring yourself that works just as well. It is helpful to have a friend since you will be measuring your back. In order to correctly asses your torso length, use a tape measure to find the distance between your iliac crest and your C7 vertebrae. To locate the iliac crest, find the top of your pelvic bone and follow it around to the center of your back. (This should be above where you think your "hips" are and below your waist.) Measure straight up from there to the knobby bone that juts out at the back of the neck when you look downwards.
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Second Ascent Pro Pack fitter Andy Dahlen demonstrates on fellow employee Andrew Magnussen how to properly measure someone for a pack fit.
Once you find that bone, make sure you stand up straight while the measurement is taken. This should give you a measurement of torso length, which you can then apply to the size of your chosen pack.

Then we suggest actually trying the pack on, ideally with weight inside. The benefit of shopping at a store is that you can walk around with the loaded pack for a while, which will give you the best idea if the pack is correctly sized and comfortable. However, if you cannot shop at a store or try on the pack that you want to purchase, careful measurements can ensure that you pick the correct size.

Lastly, double check if the pack you are considering has an interchangeable hipbelt. The hipbelt is where 80% of the weight should be resting, rather than on your shoulders, so a snug fit around the hips are important. Most packs accommodate a very wide range of waist sizes and a majority of customers do not need to alter the hipbelt in any way. Though some manufacturers, such as Osprey, offer different size options that can be swapped out for people with particularly narrow or wide waists.

Pack Weight Distribution

Once you have your pack loaded up and on your back, you will notice that you have to lean slightly forward. This is a normal and natural response by our bodies to manage the increased load. As you ascend steeper terrain, you will notice that your body will adjust by leaning even slightly more forward than when hiking on flatter terrain. In this body position, the majority of the weight should fall on your hips; roughly 65-80% of the weight. The rest of the weight should be spread out along the fronts and tops of your shoulder strap. This is the reasoning for getting a pack that not only fits around your hips but that wraps around your shoulders well.


While having a lightweight pack is ideal, and it is a good way to lighten the load you carry on your back, lighter packs often don't have as plush suspensions nor as comfy straps. This will matter less to someone who goes on mostly trips of two to three days and tends to pack light (less than 30 pounds). For people who tend to bring a few of the extra comforts of home, favor longer trips, or just end up taking everyone else's stuff, they will benefit greatly from a pound or more of suspension and padding. Heavier packs also tend to choose more durable materials and have more bells and whistles, so they tend to last longer than ultralight packs.

Durability is an obvious question to ask about packs and there can be quite a bit of difference in the toughness and longevity of each pack. But the truth is not everyone needs a super durable pack, nor needs to carry the extra weight that comes along with it. Ask yourself what is most important to you: comfort and durability or a light load?

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Dan Whitmore heading into Boston Basin, while pack testing in the North Cascades, Washington.

Pack Anatomy & Proper Adjustment

Knowing your way around your pack and its various features and adjustments may not affect your decision when purchasing a pack, but it does improve your life with your pack and allows you to use it comfortably and efficiently with different weight loads. Knowing how to quickly strap your detachable daypack onto your travel bag, lash your skis or trekking poles to the side, or appropriately adjust the load lifters will make a huge difference in your everyday life with your new pack. Below is a very basic chart of the parts of a pack, with the key adjustment points highlighted in red.

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The important parts of a backpack. The red straps are key adjustment points. Make sure to tighten or loosen these straps as needed, to get the most balanced fit. The adjustments will vary based on how full your pack is and can even change if you are hiking up or downhill.

Load Lifter Straps: These straps connect the top of the shoulder straps to the top of the pack, and when tightened correctly, they prevent the pack from leaning away from your back. Ideally they should be positioned at a 45 degree angle.

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Sternum Strap: The sternum strap clips over the chest, connecting both shoulder straps in the front. This enhances stability. Some packs allow for this strap's height to be adjusted to that it sits comfortably on your chest.

Compression Straps: These tighten along the sides of a pack. They should be extended when a pack is very full and cinched down when a pack is almost empty. These allow for the wearer to achieve a balanced pack even if it is not completely loaded down. These are one of the main features that make a pack versatile enough for a day hike or a multi-day trip.

Hipbelt Stabilizer: This strap can be tightened around the hipbelt, improving balance and comfort.

The last important parts of a pack are the load bearing parts. These days external frame packs are no longer popular, and all modern packs have internal frames, which carry closer to the body. Internal frames provide support in a couple different ways:

Aluminum Stays: These are thin support rods that run the length of the pack to give it shape and stiffness.

Framesheets: This is a thin, semi-rigid piece of material that lines the back of a pack, keeping the pack's shape and preventing object from jabbing the wearer through the fabric. Some packs have removable framesheets, while others have this piece built in. Often packs will use both a framesheet and aluminum stays to provide support.

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A pack with a removable framesheet and support stay. On the right you can see the gold aluminum bar, which when inside the pack, runs along the spine providing support while the rigid gray framesheet gives the pack shape and helps distribute the weight and support.

Perimeter Frame: These packs have a thin amount of aluminum tubing contouring around the outside of the pack on the backside. This can also help achieve an airflow design that sits the pack off of the back to prevent sweat from building up on the back.

Styles of Packs

There are many styles of packs beyond models for backpacking. For many activities you will most likely want a sport-specific model: a ski pack for skiing or a climbing pack for climbing. Or your needed gear-carrying capacity will dictate your choice. Here we detail different styles, what makes them unique, and why you may or may not want one of these particular packs.

Backpacking Packs

Backpacking packs are designed to carry large loads (30-50 pounds) for multiple days and usually range between 50-80 liters in capacity. If you plan to hike long distances with smaller loads, see below for ultralight pack tips. Packs for backpacking are designed with an internal frame and usually offer a suspension with many adjustment points in order to most comfortably carry whatever weight you are toting. The primary adjustment points are: hipbelt, shoulder straps, sternum strap, compression straps, and load lifters. Often a pack for backpacking comes with separate compartments for certain types of gear, such as sleeping bag compartments or straps to lash a sleeping pad to the outside. These packs almost always come with some type of hydration bladder compatibility and usually also offer water bottle slots on the sides so that you can choose your own water carrying method.

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Pack testing in the North Cascades, Washington.

This style of pack is offered in multiple sizes, usually S, M, and L, and you can find the correct fit for you by measuring your torso length. Selecting the correct size is vital to the comfort of one of these large packs (see above for more details on sizing) as well as knowing how to properly use it. These packs will often be too heavy and too large to cross-over into other activities well, but for multi-day trips with a lot of gear they will offer the needed capacity, support, and comfort. For more on these types of packs, reference our Review of Backpacking Packs.

Ultralight Packs

Ultralight backpacking is for those experienced hikers that want to reduce weight and carry only the barest essentials. A 30-50 pound load is considered a luxury, heavyweight load, under 20 pound base weight (pre-consumables such as food and water) is lightweight, and under 10 base weight is ultralight with under 5 being extreme minimalist. The first place to reduce weight is in your pack. Large 70-80 liter packs can weigh upwards of 5 pounds themselves, so reducing the capacity and weight of your pack is a surefire way to lighten your load. For an ultralight hiker, a 65 liter pack should be the largest capacity needed, even for a multiple day trip, and 40-50 liters is even more common. Look for a streamlined, lightweight model without many frills or unnecessary features. Ultralight models tend to offer less organizational options and will require more thoughtful and creative packing. Be aware that minimalist packs usually use thinner, less durable materials than heavier designs, so your ultralight pack will not last as long as a traditional backpack, however the saved strain on your shoulders is probably worth it. Like most packs, ultralight models come in multiple sizes, and most incorporate a hole for a hydration bladder hose.

Women's Specific Packs

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We found the top lid on the Ariel to be great for holding down climbing ropes as well as extra layers or gear.
Though women can easily wear unisex packs or appropriately sized men's packs, sometimes products designed with women in mind fit better and are more comfortable. Packs are no exception. As noted in our Review of Women's Packs, female specific packs tend to be designed with shorter torso lengths, narrower shoulder widths, and curved waist belts that are mindful of women's hips. These size and fit adjustments make it easier for females to find a comfortable pack that allows them to carry for long distances, so women's specific packs are an option worth exploring for females in the market for a pack.


Daypacks may just be the most versatile style of pack. With a capacity of 30 liters and under, these packs can be used for many activities, from a day hike to biking, fishing, climbing, and any other short adventure you can dream up. Some daypacks come with features tailored to specific activities, such as trekking pole attachments for hikers or helmet attachments for bikers, but almost any small pack can be easily converted to use for any sport. The only thing they don't do well is carry loads for multi-day trips.

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Carrying necessities for a short day's activity through the Buttermilk Boulders with the Osprey Talon 22 and the Mountain Hardwear Crimper.

Most offer some type of hydration pouch compatibility, and many newer models offer some type of back panel ventilation to make for a more comfortable, less sweat-inducing hike. Daypacks often come in only one size, though the larger models (around 30 liters) sometimes can be found in multiple sizes. We put a selection of these little numbers to the test in our daypack review, which you can read for more details on what makes the perfect small pack.

Hydration Packs

Almost all modern packs are equipped with some type of hydration compatibility. At the very least, a hole for a hose is incorporated just in case you intend to carry a bladder. However, there are also packs designed specifically for hydration, and these are essentially very small daypacks offered in only one size with integrated bladders and hose systems for quick drinking. Some hydration packs have room to store and carry other items, while others just offer a minimal carry method for water.

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The Osprey Talon has an entire separate compartment for the hydration bladder that is easy to access. This is ideal if the bladder gets wet while filling, because the main compartment of your pack stays dry.

An excellent alternative is to add a bladder to a daypack, which leaves you with a larger capacity for extra layers and a lunch while still having the added benefit of quick access hydration. A hydration pack is ideal for a biker who may not want to take his hands off the bars or for runners and hikers on the go that want to stay hydrated without much fuss and don't need to carry many other items. For products specific to carrying fluids, reference our hydration pack review, which covers many styles, from vests to models that store the water in the waist belt.

Climbing Daypack

Affectionately know as "bullet packs" after one of the most popular models, the Black Diamond Bullet, climbing daypacks are useful for long, multi-pitch rock routes that require food, water, and extra layers to be brought on route. They are simple, burly, and utilitarian.

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Chris Simrell leading off with the BBEE on Pitch 2 of Apron Strings (5.10b), The Chief, Squamish.

Ranging from 12-20 liters in capacity and coming in only one size, these little packs differ from traditional daypacks because they are designed to be low-profile, extra durable, and have features tailored to climbers such as attached daisy-chains and straps for rope attachment. They also forgo stretchy mesh pockets and bungees on the exterior because, while great for hiking, those features are likely to get snagged and torn during the rigors of climbing. Incredibly useful for toting necessities when you leave the deck, these simple packs eliminate excessive features like laptop sleeves and water bottle pockets, and many even cut out hydration compatibility in favor of simplicity. Refer to our Review of Climbing Daypacks to see which models we like best.

Mountaineering & Alpine Climbing Packs

Mountaineers, ice climbers, and alpine climbers will need a larger pack than a climbing daypack when they head out to climb, and they will also require special attachments that are superfluous on other styles. All alpine climbing models offer ice tool/ice axe attachments, crampon attachments, and range from 25-55 liters in capacity.

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Max Neale approaching Mt. Katahdin, Maine with the Hyperlite Mountain Gear Ice Pack.

Alpine packs are designed for both hiking and climbing, and in general sacrifice hiking comfort for simplicity while climbing. They typically also offer methods of stripping down to shed bulk and weight, such as removable lids, waist belts, and frame sheets that double as bivy pads. This way the pack can hike a full load with tent and sleeping bag to an overnight camp, then can be minimized and used as a lighter, smaller summit pack the next day. The preferred style of climbing will dictate the capacity needed, and one climber may need more than one, a small capacity model and a large one. For more specific details on how to choose the right pack for alpine climbing and which ones we love, read our Review of Mountaineering and Alpine Climbing Packs.

Skiing Packs

There are many kinds of packs aimed at skiers and snowboarders. Most of them are for riders heading into the backcountry that have storage for shovels and probes, and they usually have ski or board carry features for when the approach requires a bootpack. They range in size from small 20 liter side-country daypacks that have just enough room for avy gear and a water bottle to 40 liter packs with enough capacity for overnight gear.

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Another day of airbag comparisons and another day that Ryan O'Connell has a big smile on his face.

Then there are the ski packs that also incorporate technology to help increase chances of survival in the event of an avalanche, such as Avalung or avalanche airbag packs. These provide storage for your gear as well as a deployable airbag or Avalung tube, which unfortunately cut down on the capacity inside. Avalanche packs are heavier and less roomy than ski packs without this feature, but how many packs have the potential to actually save your life? Because of this added weight and bulk, these types of packs do not cross over well into other activities like hiking or climbing, but they are likely worth it for the frequent backcountry rider. Note that avalanche airbag packs will require the refilling of compressed air canisters, which is more maintenance than a pack typically requires.

Travel Packs

What if you intend to travel, take the classic "backpacking through Europe" trip rather than spend all your time sleeping in the woods? Will a regular, large capacity backpacking pack work for you?

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Travel Pro: An old photo of Amanda as she finishes up a six-month-long trip through Europe. An avid traveler, she lived out of this Mountain Smith pack for months on end on several trips. This experience helped her evaluate the packs in this review!

Often, people will just take a typical pack for backpacking with them for long-term travel, but there are some clever market offerings for travelers that can make the hassles of going from place to place just a little easier. These travel-specific designs have features such as detachable daypacks that can clip to the front of the pack for easy kangaroo-style carrying, padded carry handles, lockable zippers, and covers that zip up to protect shoulder straps from airport luggage escalators. We discuss packs with these features in our Review of Travel Packs. Alternatively, our carry-on luggage review also highlights some pieces of wheeled luggage that convert to backpacks for easy carrying once you hit the streets. Some of these pieces of convertible luggage also have detachable daypacks so you don't have to drag your whole clunky bag with you everywhere, but can leave it in the hostel and just bring your wallet, lunch, and rain jacket with you as you go sightseeing. These types of specialized travel bags don't cross over very well to outdoor use such as hiking or overnight trips, but they can make the ideal bag for bringing on a trip, depending on your style of travel.

Laptop Packs & Messenger Bags

Carrying a laptop isn't necessarily an outdoor activity, but it is a very common, important activity that a backpack can help greatly. Laptop packs have padded sleeves where you can safely and comfortably store and carry your computer whether you are walking around campus, commuting by bike to work, or freelancing from a coffee shop. Typically offered in one-size-fits-all but in varying capacities, laptop bags usually feature other briefcase-style organizational details such as pen holders, coin pockets, and key clips. They also lean towards a more professional styling versus a techy, outdoorsy appearance, so you can still look chic when heading to the office or a business meeting.

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Lita Collins and the Timbuk2 Swig on its way to Hanalei Bay, Hawaii.

When it comes down to choosing either a pack or a messenger bag for your laptop, we suggest a backpack because it is more stable, more comfortable to carry, and has a larger capacity for other belongings than a messenger style bag. Messenger bags are better when you require quick and easy access to your belongings. You can check out our Messenger Bag Review and Laptop Pack Review for more details on these styles of carry.


After taking into account the main considerations of capacity, style, and fit, you should be well on your way to the perfect pack (or packs) for your life and activities. Don't forget to educate yourself on the possible adjustments and functions of your new pack so that you can make the most of it, and enjoy!

McKenzie Long
About the Author
After graduating from University of Cincinnati with a degree in graphic design, McKenzie moved to the mountains to spend as much of her time climbing as possible. It started with an internship at Alpinist Magazine and a move to Jackson, Wyoming where she fell in love with the peaks of the West. Now she lives in Mammoth Lakes, California and runs her own freelance design business, where she is constantly balancing work and play.