Backpack Buying Guide
Choose a backpacking backpack that is right for you
A backpack is your home for the length of your backpacking trip. It holds your shelter, clothes, food, and all other necessities and comforts. You may be using your pack for backpacking a thru-hike, an overnighter, or just anything off the beaten path. But in any case, choosing the right backpack for your body, planned uses, and gear system is essential to an enjoyable experience in the outdoors.
Choosing the Capacity
When selecting a backpack to purchase, selecting one with an appropriate capacity, or volume, for you personally is essential. Use the questions below to help find what capacity would be right for you.
- What duration of trips do you plan to use it on?
Think how long of trips you plan to use the backpack for in order to determine what capacity you need. Keep in mind that shorter trips will require less gear while more gear, such as clothes and food, are needed for longer trips. If you plan to use it generally for trips lasting 2-4 days in mild 3-season conditions, you will likely need a backpack ranging from 40-75 liters. For trips lasting 5 days or more, you will want to purchase a pack with at least 80 liters. The following table gives general guidelines to what pack size would be needed for a certain trip length. However, the capacity you need depends on what type of gear you own and its size may change (see below). - What time of year to you plan to use the backpack?
For mild to moderate Spring, Summer, and Fall conditions, the guidelines mentioned above should be appropriate. However, if you are planning to backpack in extreme heat or cold, you may want to plan to have a higher capacity backpack to accommodate extra food and liquids, more clothing, a warmer sleeping bag, and a stronger tent. - What type of other backpacking gear will you pack it with?
If you already have a your backpacking equipment, you want to be sure it will all fit in the desired backpack. Many outdoor stores will let you bring your gear in, load your gear in your backpack, and walk around. This is a great option to know what capacity you really need. If you are updating or starting your system from scratch, consider purchasing lightweight or even ultralight gear.
Pack type |
Trip duration |
Pack capacity |
Pack capacity |
|---|---|---|---|
Multiday |
2- 4 days in |
40 - 75 |
2,400 - 4,600 |
Extended trip (men) |
5+ days |
80 and up |
4,800 and up |
Extended trip (womens) |
5+ days |
70 and up |
4,300 and up |
Measuring Capacity: Backpacks often contain a number in their name, such as the Osprey Mutant 38, which describes the capacity, or volume, inside the backpack in liters. They have become the standard unit of measuring, putting cubic inches in second place. This number embedded in the name is the capacity of the medium size, with each size differing by 3 liters.
Mindset: The "ultralight" mindset is made up of advanced gear and the willingness to give up conveniences for a low pack weight. Going "lightweight" is balancing weight-savings with comfort features. The "deluxe" mindset is giving up a low pack weight for comfort and convenience. It doesn't matter which mindset you have, but finding the right size and capacity of backpack is. You must find the a balance between weight reduction and comfort to fit you.
Frame Types
These days, almost all backpacks feature an internal frame design, however external frames are also available. The close-fitting and flexible design of an internal frame backpack enhances your balance and keeps your load stable on any terrain. This is ideal for many activities, such as mountaineering, skiing, scrambling and hiking in rough terrain. Internal frame backpacks also allow for more movement, letting your arms swing freely because of the narrow profiles. On the other hand, external frame packs help backpacks carry heavy loads. They also are divided into compartments, making it easier to organize and find items inside the pack compared to the single, main compartment of internal frame packs. External frame backpacks still exist, although they are hard to find as retailers are attempting to move away from them.
Fitting the Backpack
The key to comfort is a good-fitting pack. To get started, have a friend help you measure your torso length. Torso length is measured from your shoulders to the top of your hip bones. Visit the Sizing and Fitting a Backpack article for more information on correctly sizing a backpack.
Your waist size also matters, though most hipbelts can be adjusted to fit a wide range of waist sizes. Just make sure the hipbelt is comfortable when you try it on.
Many packs allow you to fine-tune their torso fit via easily adjustable suspension systems. The alternative is a fixed-suspension pack. This type is non-adjustable, but offers the advantages of being less complex and thus lighter than a comparable adjustable model.
To ensure that your pack fits properly, visit our Sizing and Fitting a Backpack article for in-depth information.
Other Key Features
Support (stays or framesheet): Typically, one or two aluminum stays are used to transfer the weight of the load to your hipbelt. Stays are typically a rod or bar, though some now feature a tubular design to reduce weight. Other packs use a stiff plastic HDPE (high-density polyethylene) framesheet for load support. This thin sheet helps prevent objects in your pack from poking you in the back. A number of packs now offer a stay/framesheet combo.
Suspension system: This refers to the load-supporting system of shoulder straps, load lifter straps, a sternum strap and stabilizer straps. Packs offer either Adjustable or Fixed Suspension. Adjustable Suspension allows you to fine-tune the fit of your pack to match your torso size. Many feature a ladder-type system of rip-and-stick closure that let you move the shoulder harness up or down in small increments. Visit the Sizing and Fitting a Backpack article for more information about adjusting the suspension system on your backpack.
Ventilation: Internal-frame backpacks hold the pack close to your body, restricting air flow and allowing sweat build-up on your back. On the other hand, external-frames allow more air flow. Many backpacks now feature ventilation systems to help fix this problem, including tension-mesh suspension system to create a permanent air space between your back and the pack. Other packs feature a channel design to provide a similar cooling effect and improved breathability.
Packbag: The materials used in packbags seek to find a balance between durability and weight. Nylon packcloth and Cordura, a burly nylon fabric with a brushed finish, both emphasize abrasion- and water-resistance. Cordura is tougher and a bit heavier. For ultralight travelers, newer fabrics such as silicone-coated nylon are used to trim precious ounces at the cost of some durability.
Top lid: This top pocket offers extended capacity, as do expansion collars. Some lids detach to double as waistpacks for day trips from base camp.
Hydration compatibility: Most packs have a compartment designed to hold a hydration reservoir, plus a port (opening) on each side to route the sip tube. Reservoirs are typically sold separately, except on hydration-specific packs. Other packs have elasticized mesh "holsters" on their sides to hold water bottles.
Hipbelt: The hipbelt should straddle your "iliac crest" - the two prominent bones on the front of your hips. This is the area where your pelvic girdle begins to flare out. When evaluating hipbelts, consider their comfort and adjustability. Some packs offer interchangeable belts, permitting a more customized fit, and even belts where the angle of the fit can be adjusted. An increasing number of hipbelts have pockets for easy access to your energy food, digital camera, GPS or similar items.
Other load-bearing straps: Most packs help keep the load close to your body by using load-lifter straps. These are located just below the tops of your shoulders (near your collarbone) and should angle back toward the pack body at about a 45 degree angle. Also common is a sternum strap which secures across your chest to help support the load and allow your arms to swing freely.
Attachment points: These allow you to attach gear to the outside of your pack if you have the need. Climbers and early-season hikers should look for ice-axe loops, daisy chains (a series of small loops where you can dangle gear, such as carabineers) and crampon patches. A shovel pocket holds a snow shovel or other items tight against the back of your pack; it's a good place to stash wet things. All of these extras, of course, add some weight to a pack.
Rain covers: Backpack interiors are waterproof treated, yet during a rainstorm water can still get through seems and zippers. You may simply use a trash bag, but many packs have a rain cover to shelter your pack from bad weather and help prevent lashed-on gear from snagging on brush.
Additional Resources
- Wild Backpacker - Sizing and Fitting a Backpack
- Wild Backpacker - How to Pack a Backpack
- REI: Expert Advice - How to Choose a Backpack
