Are you looking for a sub-three pound ultralight backpack? What about less than two?! You've come to the right place! We chose the top 12 models on the market and compared them side-by-side in the field. All the packs in this review weigh under 2.5 pounds, as this is what we decided categorized a specifically ultralight pack. Though it is still a relatively niche category concerning backpacking, there are still lots of options for ultralight backpacks out there. From Southern Utah to the Sierra Nevada to the Appalachian Trail, we used and abused these packs. All the while, we made notes of their durability, comfort, features, and ability to support heavy loads. We also conducted our own measurements to make sure they measure up to the manufacturers' claims. We have done the footwork and the research, so read on to determine the best option for your next adventure.
The Best Ultralight Backpacks for 2018
Analysis and Award Winners
The ultralight market is constantly changing, so we've gone through our review to make sure our selections are still current and added some new models to the mix. The brand new Osprey Exos 48 continues to provide excellent performance for the price and remains our Best Buy winner. But we do have a new front-runner! The Gossamer Gear Mariposa stood out for being comfortable and durable, and still only 2.5 pounds. Keep reading below to see why we liked it so much, along with some other choices for those looking for the lightest possible option or something for overnight trail runs. We've also added in the new Osprey Levity, which you can read more about below.
Best Overall Model
Gossamer Gear Mariposa
Though each model in this review shines in one way or another, the Gossamer Gear Mariposa scored highly across the board. This pack exceeded expectations regarding comfort, whether it was saddled up with a 30-pound load or carrying water and snacks on a day hike. The Mariposa has the ideal set of features — pockets just where you want them, an aluminum frame, and an extra-cushioned waist belt. We were also impressed with the Mariposa's durability, and the 100D Robic nylon (used throughout most of the pack) was highly resistant to abrasions and wear. Even after several trips through Alpine 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 all 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, cannot 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 was one of the most affordable packs in this review. It had 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 3 pounds 1.6 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. With only 48L of volume, it's not a great option for people that are still packing bulky sleeping bags and full tents either. 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 carry 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 the lightest backpack we tested that can comfortably carry 20 to 30 pounds when you need it to, but excels when carrying 10 to 20 pounds. Weighing 21 ounces, it is a half pound lighter than any of the other top scoring packs in this review. Built with a hybrid Cuben fiber material and carbon frame components, this is the pack several of our thru-hiker testers chose for multi-month hikes where every ounce mattered. The Arc Blast has received some minor updates lately, including changes to the volume (formerly known as the Arc Blast 52), frame, and belt, sternum, and top strap buckles. We have detailed these changes in the individual review of this product.
The design and features on the Arc Blast are minimal - there's no hydration sleeve or waistbelt pockets (those are extra). The frame is also intricate, and we don't recommend removing it when looking for an even lighter daypack option, as the hassle is not worth the weight savings. Finally, it only carries a bear canister vertically, which makes packing less efficient. But, if you are an experienced ultralight hiker seeking to spare another half pound or more from your Big Four base weight, the Arc Blast receives our highest recommendation.
Read review: ZPacks Arc Blast 55
Honorable Mention for Multi-Day Trail Running
Ultimate Direction Fastpack 30
The Ultimate Direction Fastpack 30 is the smallest pack we tested in this review and the only model purposely designed for multi-day trail running adventures. It has a vest-suspension design with double sternum straps but no hip belt, and it's made to carry your overnight gear for a multi-day running/fast-packing trip but little else. It's packed with features to make this easier (because actually running with a pack usually isn't easy), and you can stow a lot of gear and/or water on the shoulder straps leaving less weight behind you.
We carried up to 15 pounds in the Fastpack during a two-day trip and remained relatively comfortable, but anything more than that and your shoulders won't be happy. Its 30L volume is not that big, but if you can get your base weight down to about 6 or 7 pounds, this has more than enough room to fit your sleeping bag, bivy sack, Jetboil, layers, food, and water. If ultralight overnight running is calling you, the Ultimate Direction Fastpack 30 may be the perfect option.
Read review: Ultimate Direction Fastpack 30
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 own 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 carry 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 individual 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 pack 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 bulky 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!
A number of 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 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.
Still not sure? Take a look at our buying advice article for more info.