Looking for the best ultralight backpack to replace that five-pound behemoth in the closet? You've come to the right place. We waded through scores of the lightest packs on the market and whittled it down to the top 12 models to purchase and take out into the field for hours of testing. Almost every model in this review weighs under 2.5 pounds — our designated cut-off separating the ultralight elite from the standard backpacking fare. This small, niche subcategory of backpacking packs is growing every year, and the line between ultralight packs and traditional backpack packs is becoming more and more blurred. This year, we have included a few more models that exist in this in-between zone. From the JMT to the Appalachian Trail, we have put these packs to the test, evaluating their performance regarding durability, comfort, features, and carrying capacity. We've put each pack to the test, evaluating manufacturers' claims; read on to learn more about our findings and prepare yourself for your next adventure!
The Best Ultralight Backpacks for 2018
This fall, we revamped our ultralight pack review. Many of the tried and true companies in the ultralight world have kept their place among our Top Picks, but this season we branched out and found some new favorites. The Ultralight Adventure Equipment CDT is our newest Top Pick Award winner for Small Capacity packs. Read on to learn more about the other packs in our most recent update.
Best Overall Model
Gossamer Gear Mariposa
The Gossamer Gear Mariposa received the highest scores across the board. Regarding comfort, this pack is out of this world, whether its saddled up with a 30-pound load or carrying water and snacks on a day hike. The Mariposa has a great feature set with pockets just where you want them, an aluminum frame, and an extra-cushioned waist belt. The pack also wowed us with its durability, and the 100D Robic nylon (used throughout most of the pack) was highly resistant to abrasions and wear. After multiple trips through endless talus fields, it still looked almost brand new.
This is a 60L pack, and you can carry up to 64L in it if you want to. That's great if you're loaded down, but part of the UL mission is to pare down the weight and size of your gear, so we didn't always need that much room. However, it can carry a bear canister, which it's smaller sister, the Gossamer Gear Gorilla, didn't do so well. So, if you travel in bear country, you will be better off with the Mariposa even if you don't fill it all the way. And while we haven't recommended the absolute lightest model as our Editors' Choice winning ultralight pack, the 2.5 pounds total weight and 14 g/L weight-to-volume ratio is still impressive, and those extra ounces gave us more comfort on the trail than any other option.
Read review: Gossamer Gear Mariposa
Best Bang for the Buck
Osprey Exos 48
The Osprey Exos 48 is one of the most affordable packs in this review. It had a well-thought-out set of features, and truly delivers when you want to carry loads of 20 pounds or more. It particularly shines with 30 plus pounds in it. It has the best suspension system of the test group and moves relatively heavy loads over long miles better than any other in our fleet.
At 2 pounds 5.6 ounces, it straddles the line of being an UL pack. It had the highest weight to volume ratio in our review, though it's still a couple of pounds lighter than most traditional backpacking backpacks. It has a relatively small carrying capacity (48L) so it's not the best option for folks still packing bulkier camping gear. Finally, we had some durability concerns with this model, and while we liked the stretchy side pockets, they quickly got holes in them. However, if you're carrying a compact but heavy kit (say you need to take a lot of water for dry days on the trail), then nothing does it better than the Exos. As an added benefit, this Osprey model is widely available from online sources and bricks and mortar retailers. If you want to buy a pack today and head out on a lightweight backpacking adventure next weekend, the Exos 48 is your best bet.
Read review: Osprey Exos 48
Top Pick for Ultralight Enthusiasts
ZPacks Arc Blast 55
The ZPacks Arc Blast 55 is an incredibly unique pack in that it weighs almost nothing, while still having the ability to carry loads up to 20 pounds. Weighing 21.3 ounces, it is almost half the size of most of the packs in this review. The Dyneema Composite Fabric (DCF) is durable, but quite stiff, and is used in a few other ultralight models. This material is very durable, except when a sharp metal edge rubs on it (like the corner of a bear box), so make sure that is noted when packing the Arc Blast. The Arc Blast has been updated a bit in recent years, most notably an increase in volume from 52L to 55L. The pack has also seen a few changes to the straps, pockets, and waist belt. We got our hands on this new version this season and found that the Arc Blast is still the top pick for those who are serious about going late.
The Arc Blast is genuinely a minimalist pack when it comes to design and features - there's no hydration sleeve or waistbelt pockets (those are extra). The super-light frame is sophisticated and we do not suggest trying to remove it to further reduce weight. Also, it should be noted that it only fits a bear canister vertically, which makes packing less efficient. But, if you are an experienced ultralight hiker seeking to spare another few ounces from your Big Four base weight, the Arc Blast receives our highest recommendation.
Read review: ZPacks Arc Blast 55
Top Pick for a Small Capacity Pack
Ultralight Adventure Equipment CDT
The newest pack from Ultralight Adventure Equipment is smaller than previous models we have tested, but still totes all the same features that make these packs some of our favorites over the years. The frameless design is only suitable for lighter loads, making the CDT a bit specific; this aside, we loved the features of this small pack. The waist belt is more substantial than most packs of this size and the materials used are still burly enough to stand up to the wear and tear of the trail. The pack works best with loads under 20 pounds and will start to feel uncomfortable with anything heavier than 25. We found that when used for its intended purpose, the CDT is a top performing pack. The Robic nylon fabric is durable yet still malleable, which we liked as opposed to the stiffer materials used in other packs.
Though we rave about the feature set on the CDT, it is minimal. So, if pockets, straps, and extras are your thing, this pack may not be for you. The simple cinch top closure does not fully seal from the elements, and it lacks a lid for extra enclosed storage. These features reduce water resistance, so the CDT is not ideal for wet conditions. Overall, this pack is designed for a specific use, but when used correctly can be a great option. Plus, as a bonus, the price is right.
Read review: Ultralight Adventure Equipment CDT
Analysis and Test Results
The 12 competitors we evaluate here include the best and most versatile packs for lightweight and ultralight three-season backpacking, as well as a couple more specialized models for specific uses. The five highest-scoring models are all great choices for thru-hiking trips that last for months and shorter trips as well. Expert backpackers will also find these packs just large enough for wintertime adventures. Read on to learn more about how we scored the packs across the test metrics and to find the top performers in each one. The rating table above shows where each ultralight pack in our review ranked in the cumulative score.
We often trade off one thing for another when making an outdoor gear purchase, and no one understands trade-offs better than an UL enthusiast. How much can we strip away from our base weight on the trail and still survive? The weight savings that you can achieve in a pack often come at the expensive of something else; for example, the Granite Gear Virga 2 was the lightest option (10 g/L) but was also one of the least comfortable to carry a lot of gear with. If you are looking for a good deal on a pack, but don't want to trade-off too much on the performance end, check out our Price vs. Performance chart below. We took the overall scores (X-axis) and plotted them according to their price (Y-axis). Those models that have a good value will be further to the right but not too high on the chart, and include the Osprey Exos 48 ($200), our Best Buy winner, and the Granite Gear Virga 2 ($140). We were also impressed with the Ultralight Adventure Equipment Ohm 2.0 ($210) which narrowly missed winning our Best Buy award.
Weight-to-volume ratio is a measure we use here at OutdoorGearLab to compare packs and luggage of differing volumes. This heavily-weighted (no pun intended!) metric gets straight to the point…how much does this pack weigh relative to the volume it carries? Two sets of data, generated by our lab measurements, comprise this metric. First, we measured the weight of each model on our digital scale. Then, we weighed each pack with all modular components in place. Next, we examined each for a frame, waist belt, or other pockets that can be easily removed to pare the weight down for light loads; we then stripped these features off of each pack and weighed them again.
The most detailed lab testing with these products was our independent measurement of pack volume - since nominal volume measurements from manufacturers are difficult to compare, we decided to perform our test. Although an ASTM standard exists for measuring pack volume and many pack manufacturers perform ASTM testing, some report the capacity of only the main pack as the nominal measurement, while others include pockets. The ASTM test doesn't provide for measuring external pocket volume, which is significant on these packs. In our experiments, we measured the volume of the main pack, the main exterior pockets, and the lid (when present).
To provide an example, the Gossamer Gear Gorilla is described nominally as a 38-liter pack and the ZPacks Arc Blast as 55 liters. However, we found these two models were nearly identical in volume, both when performing our laboratory volume testing with ping pong balls and when packing in the same kit for a five-day wintertime trip on the Appalachian Trail. The weight-to-volume ratio is the most significant contributor to total scores, accounting for 35 percent. The Granite Gear Virga 2 and ZPacks Arc Blast 55 earned the best scores. These are the two lightest packs we tested and forego many of the features that are common on other models. Neither have hip belt pockets, and the Virga doesn't have a frame. By combining an incredible weight-to-volume ratio with a surprising level of carrying comfort, the Arc Blast won our Top Pick Award for Ultralight Enthusiasts.
The ULA Circuit and ULA Ohm 2.0 earned the next best scores for weight-to-volume ratio, and they each measured a tiny bit better than the middle of the field with all their modular components in use. Both were also top performers when we compared "stripped weight" to "stripped volume." We were especially impressed by the ULA Circuit, which has a larger carrying capacity than the Ohm 2.0, but weighs almost the same. Unlike the Granite Gear Virga 2 or the ZPacks Arc Blast, both of these are fully-featured with hip belt pockets and can carry heavier loads in more comfort.
Of course, we all want an ultralight pack to be featherlight, but it must carry our load comfortably to be worth it. For each of these packs, we judged load-carrying comfort for two loads: 15 lbs and 30 lbs. We then averaged each pack's performance in both categories to generate our carrying comfort score. Fifteen pounds is a perfect comparison weight for ultralight hikers on a short trip, while thirty pounds is a fair comparison weight for lightweight hikers on shorter trips, ultralight hikers carrying a week's worth of food, or for those brave enough to travel in the winter. While some packs are capable of being stripped of their frame and waist belt, our evaluation of "great, good, or poor" for carrying 15 lbs and 30 lbs is with the frame and waist belt in use. We would recommend stripping down a pack completely when carrying 12 pounds (or less) total weight.
The Gossamer Gear Mariposa, Gossamer Gear Gorilla, and the ULA Ohm 2.0 earned our highest scores in this category, for carrying both 15 and 30-pound loads. Also, these three packs are the easiest to strip of frame and waist belt if and when you want to take 12 pounds or less. At this low weight, we feel frames, and even waist belts are not necessary.
Also notable in this metric are the next highest scorers. The Osprey Exos 48 carries 30 pounds more comfortably than any other we tested, but we found the tensioned frame a bit "turtle shell-like" for much lighter loads. The Arc Blast 55 also earned a high score. It carries 15 to 25 pounds as comfortably as any other pack, but we found 30 pounds to be a bit of a stretch regarding maintaining comfort.
- Best for 10-20 lb loads: Top Pick for Ultralight Enthusiasts: ZPacks Arc Blast 55
- Best for 15-25 lb loads: Editors' Choice: Gossamer Gear Mariposa
- Best for 20-35 lb loads: Best Buy: Osprey Exos 48
Manufacturers constantly seek to find the right balance of features for ultralight backpacks. Eliminating most creates a very light pack, but including the right features can greatly increase comfort, versatility, and ease of use. The lightest two packs we tested, the ZPacks Arc Blast and Granite Gear Virga 2, both earned top scores in our weight-to-volume ratio metric. Their total scores reflect the trade-offs required to be the lightest: reduced load carrying comfort at heavier weights and reduced ease of use as a direct consequence of eliminating features.
In our reviews, we provide a thorough description of each pack's features not covered elsewhere. When covering big miles on the trail, features like easily accessible side pockets for your water bottles, waist belt pockets for snacks, and a convenient place to keep maps handy are a huge benefit. This is also where we detail how each pack accommodates a hydration bladder and just how much stuff you can stow in the exterior pockets.
The Osprey Exos 48 incorporates so many features and it's head and shoulders above the rest. While most manufacturers pick and choose which elements they think are the most useful, Osprey provides nearly every storage, lashing, and compression feature you can imagine. This is super convenient but contributes to the pack's relatively heavier weight. The Gossamer Gear Mariposa also earned top scores in this category with its well-placed side pockets, over-the-top closure mechanism, and large mesh back pocket. Additionally, the ULA Ohm 2.0 received high scores in this metric, though the Gossamer Gear packs both have a large external back pocket, which the OHM 2.0 lacks. We love how much you can stuff in the Gossamer Gear pack pockets compared to the small volume of the Ohm's exterior pocket.
While our carrying comfort metric is focused on how well each pack can carry either 15 or 30 pounds in its full configuration, our adaptability metric focuses on other considerations when you may want to scale your pack up or down in carrying capacity. While on a thru-hike or a week-long adventure in the backcountry, your total bulk and weight will fluctuate up and down between re-supplies and for weekend trips sometimes you'll need to carry a substantial load, but other times you may carry very little. A pack whose design allows the frame and waist belt to be easily removed for very light loads is more adaptable.
While many of our testers have several packs suited for varying loads, a highly adaptable contender is critical when you seek one backpack to do it all. The Haglofs L.I.M. Strive 50 received high scores in this category due to its easy-to-remove frame and simple design. These features allow it to carry minimal weight, or be packed up with a massive load easily. The pack's overall design is versatile too; we found it served its purpose as a lightweight mountaineering pack and was a fully functional pack for backpacking.
While stripping the pack down is an excellent feature for light loads, a kit that allows you to strap bulky but light items to the outside is a bonus when you need to carry big loads. Each of these competitors has multiple ways to add things, like a closed cell foam pad, to the outside. And while in general, we are not a big fan of lids for ultralight packs, they do create one key advantage: the ability to carry bulky items on top of the main compartment secured under the adjustable lid. The Osprey Exos 48 and the Hyperlite Mountain Gear Windrider 3400 both earned a top adaptability score because of their ability to carry heavy loads well with tons of external lashing options. The Hyperlite pack also has a very tall roll top, similar to the one found on the ULA Circuit, that provides a great place to store extra bulky items when a significant food resupply occupies the main pack.
Our adaptability score also considers ease of use with a bear canister. This will be irrelevant to some, but bear canisters are required by regulation on some portions of the PCT and AT. The BearVault BV500 is perhaps the most common bear canister used by weight-conscious hikers in areas where bear-proof food storage is required in the backcountry. We loaded each pack up with a standard three-season kit and five days of food in the BV500 to see how well it fits inside and how much room is left over for the rest of your stuff. If you regularly carry a bear canister of this size, the Hyperlite Mountain Gear Windrider and the Gossamer Gear Mariposa are compatible with this can.
How durable can a sub-two-pound backpack be? The answer is that most are surprisingly durable. That said, many of these packs require a little more care and attention than load monsters that weigh five or six lbs and use much heavier fabrics and frames. If you plan to carry more than 30 pounds most of the time, the packs in our backpacking backpack review will serve you better. So how durable SHOULD an ultralight backpack be? As a baseline, to achieve an above average score, we estimated that a pack must last for a least one thru-hike of a trail like the PCT or Appalachian Trail. The best of these packs will see you through many thousands of trail miles!
Many factors go into our rating for durability, which contributes 10% of the total scores. First and foremost, we consider the types of fabric used for the main body of the pack and the exterior pockets. All of these areas are subject to abrasion, especially the pockets (if you tend to stuff a lot into them). There are always trade-offs in design; for example, incredibly light main pack fabrics are less durable than robust 200 Denier nylon ripstop fabrics.
Additionally, the stretchy exterior pocket fabrics that we love for function tend to be more prone to snagging on tree limbs or abrading on rock in comparison to non-stretchy pockets. Unfortunately, it seems that you can't have it all. In our experience, a stretchy main exterior pocket with durable side pockets is the best compromise. This type of design is found on the award-winning Gossamer Gear Mariposa.
While it is the case that you'll need to treat your pack nicely (it is your home on your back!), we also take into consideration whether sitting on it while it is loaded or rough handling in the back of your van or truck could break the frame. To this end, we think that if you are focused on durability or if you are known to be rough on your gear, you should choose a pack with an aluminum frame versus carbon fiber. The rugged aluminum frame is one of the many small factors that lead us to prefer both of the Gossamer Gear packs to the two ULA packs. The carbon rod frame found in the ULA Ohm 2.0 and the ULA Circuit is significantly more fragile. Out of our top scorers, the Mariposa and Windrider are the two models we felt comfortable sitting on without the worry of breaking something.
A rain cover for your backpack has long been one of the key accessories to ensure your backpacking kit stays dry through rainstorms. The Osprey UL Raincover is a reliable and widely available choice, as are the covers from Sea to Summit.
Waterproof roll-top style dry bags or Cuben stuff sacks are an excellent choice for both organization and moisture protection inside your backpack. Sea to Summit's ultralight Sil-Nylon bag is also an ideal choice. For those seeking to shave off the grams, Hyperlite Mountain Gear, ZPacks, and several other ultralight manufacturers produce a large variety of Cuben fiber storage and stuff sacks.
Lining your backpack with a contractor's plastic garbage bag, or better yet a trash compactor bag has long been a great option to ensure your kit stays dry during long rainy days on the trail. While one of these should last you for a week or more with a little care, you would replace it often while thru-hiking. Cuben fiber pack liners are the state-of-the-art in super light and durable waterproof pack liners. The models available from ZPacks are the best we've seen.
If you're interested in cutting weight even further, the video below demonstrates how to use a sleeping pad as a back pad in an ultralight backpack.
There are a lot of advantages to going ultralight, and we hope these analyses and assessments will help you drop weight in your kit without sacrificing the features you love. While low weight is key, it's not the only piece of the puzzle. If you need more help in narrowing down your options, be sure to check out our Buying Advice article for further tips and tricks.
— Jane Jackson & Brandon Lampley