How to Choose a Backpack
What is the best backpack for you? It depends on what you’re doing, when and where you’re going, and how long your trip is. Knowing these things will help you determine how much stuff your pack needs to carry. You’ll also need a pack that properly fits you and a pack suspension system that can handle the weight.
Note that this article is geared mostly for larger overnight backpacks. For information on smaller packs, read How to Choose a Daypack.
Choosing the Right Volume
Quite a few backpacks are on the market, ranging from small daypacks to full-size backpacks designed for six months on the Appalachian Trail. Fortunately (for your back), packs have been getting smaller over the past 20 years. This is not due to pack technology as much as advancements in camping gear. Tents are lighter, as are sleeping bags, stoves, etc.
Pack volume refers to how much space there is inside the pack, measured in liters. Many large backpacks include the volume, in liters, within the name, such as the EMS Long Trail 70 or The North Face Terra 35.
What volume pack is best for you? That depends on what you’re using it for and what you need to carry.
|15 - 30||Day hikes, school|
|30 - 50||Overnight (1-2 nights)|
|45 - 55||Weekend (2 -3 nights)|
|55+||Extended Trips (3+ nights)|
Each of the capacities in the above chart cover a wide range. A backpack for an overnight backpacking trip may require a pack anywhere from 30 to 50 liters in volume. It all depends on whether you’re a minimalist or a more traditional backpacker.
A minimalist or ultralight backpacker chooses the lightest, most compact gear, and would rather sacrifice a lot of stuff other people might regard as necessary rather than carry it on their back. Their sleeping bag, for example, is insulated with the highest-loft goose down, and they’ll most likely leave their tent’s stuff sack and tent stakes at home. And forget about taking a change of clothing.
If you’re a typical backpacker (90% of us) who takes the normal amount of gear, choose a pack on the bigger end of the scale. If you’re winter backpacking, you’ll need a much larger backpack to carry additional clothes, a warmer sleeping bag, and a heavier, sturdier tent. Also, if you’re backpacking with your kids, figure on having to carry some of their food and gear.
Liters vs. Square Inches
Volume is measured in both liters and square inches. Either method works, and many backpack manufacturers provide the customer with both.
|Liters (L)||Cubic Inches (in³)|
|Liters (L)||Cubic Inches (in³)|
What’s the Difference Between Staying Out One Night or Five Nights?
The longer you stay out, the more food and fuel you’ll need. You also may need a change of clothing in case you get wet. Other than that, you’ll still need a tent, sleeping bag, sleeping pad, stove, etc., regardless of how many nights you’re camping.
Determining Torso Size
Whatever backpack you choose, it needs to match your torso length. To determine your torso length, reach behind your neck, bend your head forward, and find the C7 vertebra. It’s the bone that sticks out the most on your upper spine. Next, locate the iliac crest. It’s the top of the hip shelf on the sides of your hips. Finally, have somebody take a cloth measuring tape and measure the distance from the C7 vertebra down to the point of your back that’s at the same level as your hips’ iliac crest. This distance is your torso length.
For the pack to fit correctly, the distance from the top of the shoulder strap to the hip belt needs to accommodate your torso length. Keep in mind that torso length is not the same as height. A tall person can have a short torso, and a smaller person can have a relatively long torso. All full-size backpacks should list a torso-length range in inches.
Some packs have an adjustable torso length, meaning the distance between the shoulder straps and the hip belt can be lengthened or shortened, while other packs have fixed torsos lengths. Also note that some packs are sold in multiple sizes and the torso lengths can vary from size to size.
For more information on proper pack fit, please read How to Fit a Backpack.
Selecting the Right Suspension
You’ve determined the proper volume and torso size. The next question is, will you be comfortable carrying the weight? This depends on the pack’s suspension. If you’re carrying 30 pounds with a flimsy hip belt, all the weight will fall onto your shoulders, and after a while you’ll be in pain. To choose the proper pack suspension, it helps to understand the different components.
When carrying heavy loads, the majority of the pack’s weight (as much as 80%) should be supported by the hip belt. Large backpacks designed for long-distance thru-hikes will use a heavily padded, relatively rigid hip belt that anatomically wraps around your hips. Smaller packs built for lighter loads have hip belts with less padding. A daypack designed for very light loads may offer only a webbing waist strap with no padding at all. Climbers and skiers may opt for a minimal hip belt to increase their freedom of movement.
To carry the weight, the hip belt should be centered over the hip bone (not the waist) and needs to be very snug. Once the hip belt is securely tightened, there should be a gap of 3 to 6 inches between the padded portions of the hip belt (over the buckle area). If the gap is too big or too small, you probably need a different pack or hip belt.Molded Hip Belts
Osprey makes BioForm and IsoForm custom moldable hip belts that can be heated up and then molded to your hips to create a perfect fit. Most Eastern Mountain Sports stores have an oven that can heat the hip belt. Even without an oven, your own body heat will help mold the hip belt over time.
The best shoulder straps curve to anatomically conform to your body shape. The padding doesn’t have to be very thick because most of the weight should be transferred to the hip belt, but it should be comfortable to wear, with no chafing or pinching.
While wearing the backpack, stand sideways to a mirror. The straps should conform to the top and back of your shoulders, leaving minimal or no air space between the pack and your body. In front, the shoulder strap padding should end about 2 to 3 inches below your arm pits. If the padding ends at or above your armpits, the straps are too short and you’ll need either another pack or different-size shoulder straps.
These straps attach the top edge of the backpack to the upper portion of the shoulder straps. Adjusting these straps allows you to lean the pack toward or away from your upper body, keeping the pack in balance over your hips. Looking sideways at the pack, you should see the load straps forming a 45° angle to the top of the pack. the angle is drastically off, you may need to adjust the torso length or choose a different pack.
This adjustable strap is located just over your sternum and connects both shoulder straps together to keep the pack steady.
This is the portion of the pack that presses against your back. All back panels should be padded to prevent the pack’s contents from poking you in the back. One drawback of a back panel is that it causes your back to sweat. To minimize this, some pack manufacturers build air channels into the back panel to allow some airflow. The panel should also be made of a porous air-mesh foam for greater comfort.
The frame of an internal frame backpack provides rigidity and helps transfer the load onto your hips. Some frames consist of two aluminum or composite stays (flat bars) running parallel to each other underneath the back panel. In other pack frames, the two metal stays cross in an X-pattern. Still other packs use thin metal rods to create a frame, located either behind the back panel or along the perimeter of the pack.
A framesheet is usually made of plastic and is located behind the padded back panel so it’s not visible. It’s often used in combination with a metal frame to give the pack vertical and torsional rigidity.
Choosing the Right Suspension
The heavier the pack load, the more you need a substantial suspension. Here’s a quick guide.
Recommended Suspension (by packed weight):
Up to 10 pounds = minimal suspension; no frame, no padded hip belt
10 to 20 pounds = light frame (rods), framesheet, lightly padded hip belt
20 to 40 pounds = moderate frame (stays or rods), moderately padded hip belt
40+ pounds = substantial frame (stays or rods), thickly padded hip belt
Adjusting the Fit
If a pack doesn’t fit correctly, nothing else really matters. It’s like a pair of boots—they can be the best ever, but they’re not much use to you if they don’t fit. Likewise, a pack needs to properly conform to your body and allow you to carry the weight on your hips, not your shoulders.
Here are some quick pack-fitting pointers:
Your body’s torso length should be within the pack’s torso range.
The shoulder strap should conform to the back of your shoulders.
The load lifter straps should come up off the pack at a 45° angle.
The shoulder strap padding should end 2 or 3 inches below your armpits.
The hip belt should cover the top of your hip bones (iliac crest).
The hip belt should support the majority of the pack’s weight.
Compartments & Pockets
Backpacks offer a wide variety of storage compartments, pockets, and sleeves. Some backpackers like a simple, streamlined pack with one main compartment. Others prefer having multiple places to stash their phone, food, water bottle, etc.
This is the largest space in the pack. It’s where your tent, food, stove, fuel, and most of your gear are stowed. Most large backpacks allow access from the top. Some travel packs, plus many smaller daypacks, are panel loaders, providing access from the front of the pack.
Sleeping Bag Compartment
The sleeping bag is usually stowed within the bottom of the backpack. Many packs have a sleeping bag compartment that’s separate from the main space.
Top Lid—This pocket also keeps rain out of the main compartment.
Front Pockets—Many packs have a large front pocket with a zippered closure. Others offer a “shovel” pocket, which accommodates a bulky jacket.
Side Sleeves and Pockets—When combined with side compression straps, side sleeves can hold tent poles. Larger sleeves can also hold water bottles.
Hip Belt Pockets—Nice for keeping small essentials within easy reach.
Other Things to Consider
How to Load a Backpack
How you position the different items within the pack goes a long way to determining how comfortably the pack will carry. The heaviest items, such as water, food, the stove, and fuel, should carried close to the back panel and at the vertical midpoint (or higher) in the pack. The lightest items can be carried away from the body.
For more information, read How to Load a Backpack.
Large backpacks should be tall and narrow. This allows for greater stability and freedom of motion.
Nylon and polyester are the most popular pack materials. The higher the denier, the stronger (and heavier) the fabric. The bottom of the pack should be made of a high-denier fabric to withstand abrasions.
Besides coming in smaller torso sizes, women-specific packs should have shoulder straps and hip belts designed to better fit a woman’s body shape.
External Frame Packs
External frame packs have an easy-to-spot metal frame on the outside of the pack. Because they’re wider and carry farther away from the body, they’re less stable than internal frame packs. They’re easy to organize, however, and because of the space between your body and the pack, your back won’t get as sweaty.
Some packs have an interior sleeve specifically designed to hold a hydration bladder. A hydration-compatible backpack should also have a hydration port (a small built-in hole) to accommodate the rubber drink tube.
Compression straps are found along the sides of the backpack. They cinch down, pulling the contents within the pack toward the body for better balance and stability.
A pack’s side compression straps can often be used to carry skis. Simply slip the skis inside the straps and then cinch the straps down. There are also a few packs that can carry a snowboard.
This collar extends from the main compartment upward, letting you stuff more gear into the pack. Packs with a spindrift collar can often be stuffed beyond their stated volume.
Bungee cords, clip-on points, daisy chains, and ice axe loops all allow you to strap or clip extra clothing and gear to the outside of your pack. Keep in mind that if you’re scrambling through bushes and other obstacles, these attachment points might catch.
Unless you’re backpacking exclusively in the desert, buy a rain cover sized to fit your backpack. Because of all the seams, backpacks are not waterproof.
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