At Tortuga, our mission is to make travel easier. Our advice and recommendations are based on years of travel experience. We only recommend products that we use on our own travels.
This article is your quick guide to understanding travel backpack sizes.
Most backpacks are between 20 and 85 liters. That range is huge. So what size is best for traveling?
Small bags, starting around 20L, are best used as daypacks. They work well when you’re only carrying a few items that you need to keep handy, like a light jacket, a camera, or snack. Twenty-five liter bags can also be used for short weekend trips if you’re a light packer.
Extra large bags, 65L and up, are for long hiking trips. These bags work well in the outdoors when you will be carrying multiple days’ worth of clothing, food, and camping gear.
But bags larger than 65L are way too big for travel, even on extended trips. If you’ll be traveling for more than a week or two, you’ll need to do laundry anyway. You can’t—or at least shouldn’t—try to carry a month’s worth of dirty clothes.
Between these two extremes is the sweet spot of backpack sizes. A 30-40L backpack is perfect for travel. Keep reading to learn why and how this size can save you money.
Tortuga
Carry-On-Sized Travel Backpacks
4.7
Pack for trips of one week or more without checking a bag.
Pros:The Best Size is Carry On Size
If you have to check your bag, you’ll pay checked bag fees, wait around at baggage claim, and risk lost or damaged luggage. Instead, travel carry on only.
The ideal travel backpack is carry-on-sized for:
Airlines’ carry on limits are either defined in volume (liters) or dimensions (inches). Some airlines also publish weight limits.
Airlines will vary by volume, dimensions, or weight. The above is a good rule of thumb, but always check your airline’s rules before flying to avoid any last-minute surprises.
Bags larger than 45L cannot be carried on. If you see a 50L backpack marketed as a carry on, double-check the dimensions. It’s probably too big to technically qualify as a carry on. Most airlines won’t measure your bag or look too closely at it if it’s close to the limits. But we recommend obeying the rules so that you never have to worry about whether you’ll sneak by the gate agent or not.
Packing carry-on-only might seem daunting at first, but packing for a long trip in a carry on backpack is totally doable with a little preparation. If you’re new to carry on packing, start with the Step Down to Carry On series.
Tortuga
Carry-On-Sized Travel Backpacks
4.7
Pack for trips of one week or more without checking a bag.
Pros:The Right Size Travel Backpack
While researching bags for a backpacking trip in 2009, we were surprised to discover that most backpacks were too big to be carried onto a plane. Large backpacks were mostly made by outdoor companies without regard for carry on rules. No one was designing bags for city travelers like us.
The perfect travel backpack didn’t exist; so we made it.
Every backpack that we make is a carry on. Even when fully packed, the max dimensions for our 45L bags are 22 x 14 x 9 inches—exactly the size that most US airlines allow.
The Tortuga’s Travel Backpack combines the ergonomics and portability of a backpack with the obsessive organization and easy packing of a suitcase. With the Outbreaker, you’ll have a place for everything. For a perfect fit, the Outbreaker is height-adjustable so you can have a perfect fit even if a carry on backpack looks big or heavy to you.
The Travel Backpack is our most ergonomic, most organized, and most adjustable backpack. The 40L will max out carry on dimensions on most airlines so you never have to check a bag. For stricter airlines, like RyanAir, 30L will be a better choice.
Peak Design's 45L Travel Backpack ($299) is a modular backpack designed for travelers and photographers. Out of the box, the bag can hold 35L of cargo (meeting international carry-on size requirements), but then expands to 45L to carry even more. There's a slot for laptops up to 16" in size, plus specially-designed cubes (sold separately) to carry loads of photo and video gear. The bag is smartly designed, aesthetically sharp, and packed full of unique design features.
Will the Peak Design 45L Travel Backpack be your next camera bag? Let's take a look and find out.
Pros
Cons
Disclaimer: Peak Design provided the backpack and storage cubes for this review. All opinions are my own.
Introduced through a crowdfunding campaign back in 2018, the 45L Travel Backpack is part of Peak Design's "Travel Bag" line which includes a smaller 30L sibling, a larger 65L "duffelpack" (hybrid duffel and backpack), a traditional duffel, and a small collapsable tote. All bags have the same, distinctive Peak aesthetic: sleek, sharp, and thoughtfully designed.
The 45L Travel Backpack is primarily designed for...you guessed it: travel. A rugged, expandable bag made for weekend getaways, vacations, and extended trips. The right bag for those who need to carry more stuff than what an everyday backpack can hold, but aren't going to go mountaineering or hike for long periods of time (the bag may be a bit large and bulky for the former, but also not quite customizable or comfortable enough for the latter).
Nylon material in the 45L Travel BackpackThe outside of the bag is made of 100% recycled, water-resistant 400D nylon canvas, plus thicker 900D nylon canvas on the bottom. The 900D nylon is more water resistant and helps keep the bag dry when placed on damp ground.
The 45L Travel Backpack has three straps: shoulder, waist and sternum. The sternum strap is adjustable, with four positions to accommodate different torso lengths (I'm tall, so I moved the sternum strap to its lowest position). The waist and shoulder straps are not height adjustable. When not in use, both the shoulder straps and waist belt may be tucked underneath clever, magnetized side flaps (pictured above) to clean up the bag's exterior appearance.
At the time of this review, the 45L size is sold in two colors: black and sage. Normally I prefer monochromatic gear, but was pleasantly surprised by sage (looks like soft heather gray with a touch of green). Sage elevates the pack's aesthetic and makes the bag look more premium and unique. I like it!
Travel Backpack Laptop SleeveInside the bag is a spacious cavity for all types of gear, various zippered pouches for small items, plus a velcro-enclosed laptop sleeve. The sleeve is just as wide and deep as the pack itself and provides plenty of space for 16" laptops or smaller.
As a brand, Peak Design is known for smart and clever design ideas in all their products, and the 45L Travel Backpack is no exception. Throughout the bag are small details that collectively add-up to provide a unique, thoughtful user experience. Here are a few of the details I noticed.
Hidden side pocket in Travel BackpackPeak Design added a small, barely noticeable pouch (pictured above) to one side of the bag's back. It's super thin and small; perfectly sized for a business card, cash, passport, or (my favorite use) an Apple AirTag to keep tabs on the bag in case I leave it behind somewhere or someone runs off with it.
Side handle on the 45L Travel BackpackDiscrete handles are on the left, right, bottom and back (pictured above). These handles are more secure and comfortable when carrying the bag one-handed instead of carrying it using the shoulder straps.
Side pocketsThe stretchable pockets on the left and right side of the backpack (pictured above) are taller than other camera backpacks I've used. The extra height helps better secure items like large water bottles and compact tripods.
Straps in lower flapFor taller items in the side pockets there are two removable straps inside the lower flap. These may be unhooked from inside the bag and moved to exterior loops to help tighten down tall tripods or mount items to the front of the bag. (Note: this is an update to my video review where I said the bag could use straps. Turns out they do exist.)
The standard, FAA size for carry-on luggage when flying in the United States is 22" x 14" x 9". The Peak Design 45L Travel Backpack sits right on this line, with external dimensions measuring 22" x 13" x 9.5" (56cm x 33cm x 24cm).
As for capacity, 45L is the maximum carry-on size allowed on most airlines in the United States. International and budget airlines tend to be more stringent, limiting capacity to 40L or less. 35L would be acceptable with any airline, anywhere.
As mentioned earlier in the overview, the 45L Travel Backpack has a standard capacity of 35L, so it's actually a little smaller than its name may indicate. It's only when expanding the bag using a front zipper that capacity increases to 45L. This means the bag would be perfectly fine when used as a carry-on at its standard size, and could then be expanded for more room when arriving at your destination if need be.
Collapsing travel backpack to 30LAlso worth noting, the 45L Travel Backpack can also be compressed to a smaller, 30L size (as pictured above) for easier transport when not carrying as much gear. Simply squeeze the top of the bag for a slimmer, sleeker profile.
As mentioned earlier, carrying photo and video gear in the 45L Travel Backpack requires additional Peak Design camera cubes that must be purchased separately. Cubes are available in small ($50) medium ($70) and large ($90) sizes. This increases the overall price of the backpack for photographers and videographers, but makes the experience of packing and carrying camera gear dramatically better.
Peak Design camera cubes and gear in 45L Travel BackpackThe 45L Travel Backpack can hold three small cubes, one small and one medium cube, or one large cube. The medium cube is basically two small cubes, while the large is three. Each cube is designed to fit snug inside, with additional loops and small carabiner-like clips that secure the cubes to the bag's interior prevents them from accidentally falling out.
Peak Design camera cube clipsInside each cube are padded velcro dividers that may be repositioned to accommodate a variety of gear layouts and configurations. There's also a small, handy velcro pouch with a zipper enclosure for fiddly things like SD cards, wipes, clothes, etc.
Also of interest, the medium and large cubes have zippered openings on both sides. Once opened and with the flaps tucked under, a photographer may open the side of the backpack and access their camera without taking the pack off. This could be handy when shooting handheld while hiking.
Cubes may also be flipped around and clipped in the opposite direction (from their standard back-loading orientation) to access gear through the front of the bag. The front doesn't open as fully as the back, but works fine for those who'd rather access their gear through the front.
Side opening on the 45L Travel BackpackEach cube also has exterior handles and loops for attaching camera straps (like Peak Design's excellent Slide straps); making it possible to carry the cubes as shoulder bags.
All together, its the modularity of the 45L Travel Backpack and cubes that make the Peak Design system an intriguing option. Photographers can load up the bag with cubes and gear when flying, then remove one or more cubes when reaching their destination. This would be especially helpful when hiking, for a collection of gear could be broken down to just the essentials, with room leftover for a jacket, food, or whatever else. It also gives unpacked gear a secure place to live when not in use.
This is different from the experience of using a dedicated camera bag (like this excellent model I reviewed from Manfrotto), for with the latter, all gear and velcro dividers must be removed when using the bag for other purposes. They are more work to organize and customize, unlike cubes which may be quickly added and removed as needed.
Peak Design designed the 45L Travel Backpack to look cleaner and more polished than most hiking and camping backpacks. This is great for photographers who want to own and use a single bag for all uses cases and environments.
The shoulder and waist straps are constructed using thin, high-density foam. Both straps are perfectly comfortable for light and moderate hikes, but for me are too thin for extended hikes. I also would have preferred some control over where the shoulder straps mounted to the bag (to more comfortably accommodate longer torsos like mine).
Waist belt claspThe sternum and waist straps use unconventional metal hooks instead of the standard clasps used by other bags. The waist belt hook slides into a black strip of nylon, while the sternum strep connects to one of four "pockets" stitched into the shoulder strap. Of note, the sternum strap isn't stitched into the bag, so it can be removed (intentionally or accidentally).
For me, the waist band takes some getting used to. Though it does the job of redistributing weight from the shoulders to the hips, it feels a bit thin for my taste. I wish the waist strap was thicker and more substantive, but I also recognize that that change would detract from the bag's aesthetic.
Photographers who don't hike long distances or wear packs for extended periods of time shouldn't miss having thicker straps or a more sophisticated, customizable harness. But for photographers who wear backpacks longer in more physically demanding, strenuous environments, a different brand of outdoor camera bag may be better suited.
Overall, the 45L Travel Backpack is a thoughtfully designed bag, but there are a few limitations and particular use cases where the bag may not be the best fit for everyone.
The 45L Travel Backpack does not come with an integrated rain cover. The nylon exterior of the bag and zippers are water resistant, but not completely waterproof. This means some moisture could still get inside the bag, and some photographers would likely prefer keeping the bag itself dry (especially when caught in a downpour). For those who want true protection from the elements, a separate RainFly ($30) cover must be purchased. I wasn't able to test the cover, but it appears to integrate nicely into the magnetized front-flap compartment.
Finally, the 45L Travel Backpack provides few options for additional customization and modification of its exterior. It has a few carabiner loops for hanging things, but there are no additional mounts or slots for attaching straps or other accessories. Photographers who like to customize their bag exterior with additional pouches, straps and accessories may be better served by a more traditional outdoor backpack.
Overall, the 45L Travel Backpack from Peak Design fills a niche in the large marketplace of photographer bags and backpacks. It has most of the features of a backcountry, wilderness backpack but with a more refined, streamlined design that wouldn't look out of place in urban environments.
Hiking with the Peak Design 45L Travel BackpackThe camera cubes are clever, for a traveling photographer or videographer may use them configure their own gear layouts for different scenarios, whether that means filling up the bag with gear when used as an airplane carry-on, or modifying their setup later on the ground. The modularity and flexibility is fantastic.
Finally, for readers unfamiliar with the company, it's worth mentioning that Peak Design is one of the most serious companies about lowering the environmental impact of what they manufacture. So much so in fact they founded their own non-profit for other companies to follow. Peak Design is also fair trade certified, with standards for their workers and manufacturing facilities. Finally, all their products (including the 45L Travel Backpack) are guaranteed for life, so the company will help you out if ever there is ever a defect.
At the time of this review, the 45L Travel Backpack retails for $299 in the United States, but prices can and will change, so click the button below to check the current price of the bag through reputable online retailers (including Peak Design itself). To their credit, Peak Design also maintains a used marketplace for the 45L Travel Backpack and other products, for those looking to re-use gear and save money!
Here's the video version of this review.
Peak Design 45L Travel Backpack Review video