Gear Basics: How to Choose a Backpack

backpack selection at Next Adventure

A backpack will be one of the most important purchases you make since it is what you use to carry all of your gear, ideally in well-balanced comfort. There are many choices in pack styles, sizes, shapes and features, so take the time to find the right one for you and your gear.

What to look for when purchasing a backpack

Frame Styles

Backpack frames come in three types: internal, external, and frameless. Internal frame packs are the most readily available and common choice for the average backpacker. These packs are built to evenly balance loads and stabilize weight. External frame packs, while still produced, have for the most part gone the way of the dinosaur. Most people using an external frame pack are doing so in order to haul heavy specialty equipment such as inflatable rafts. The frameless pack is most utilized by the ultralight community. The lack of frame in this pack style allows for a significant weight savings, but frameless packs are typically not advised for carrying over 25 pounds.


A common question that a new backpacker has when purchasing a backpack is, “which capacity do I need?” The answer to that question will depend upon the typical length of your trips and the type of gear you plan to carry. It’s a good idea to purchase most of your backpacking gear before considering a backpack since you’ll need to find one that fits what you plan to take.

For most people getting started, a backpack between 50-65 liters is recommended. If you have ultralight gear, you may be able to use a 40-50 liter or smaller backpack. Keep in mind that having a pack that has extra room doesn’t mean that you have to fill it to capacity, but a pack that’s too small for your gear can’t be expanded. 


When it comes to choosing a specific backpack, it is highly recommended to go to a retailer to get fitted (ask for assistance with this) and try on multiple packs prior to purchase. Most backpacks are available in sizes that can range from extra small to large. The size is determined by torso length, not overall body size. When shopping for a pack, add weight to allow you to test it loaded. Most retailers have weighted items for this use. A loaded pack feels completely different than an empty one, and will change how it fits you.

Women-specific backpacks are made a bit differently than unisex backpacks, with a narrower and shorter torso, and a contoured shape in the hip belt and shoulder straps to fit the female build. Some women’s packs also have more padding in the hip belt and shoulders. 

Backpack Features

Pack access: most backpacks have top loader access for placing items into the main compartment of the pack through a top opening. Some offer front or side zippers for additional access to the main panel.

Ventilation: to help prevent your back from getting sweaty or overheated, some packs have a raised mesh back panel that is contoured away from your body, or a “chimney” section on the back panel to improve airflow.

Sleeping bag panel: a zippered compartment at the bottom of a pack for storing a sleeping bag. 

Top lid: provides extra storage capacity with a “lid” that sits on top of the main compartment. Top lids can be useful for carrying small items that you need frequent access to. Some can be detached and used as a day pack.

Shoulder straps: choose a pack with shoulder straps that are well padded, easily adjustable, and contoured to fit the shape of your body.

Hip belts: Since the weight of a pack rests on the hips, a well-fitted and padded hip belt is crucial to comfortable backpacking. 

Hip belt pockets: one of the most useful features on a backpack are hip belt pockets – used for storing small items for easy access while hiking.

Load lifters: located at the top of the shoulder straps and connected to the top of the pack frame, load lifters are used to keep the top of your pack from pulling away from your body.

Sternum strap: attaches across your mid-chest to connect the shoulder straps and prevent your pack from shifting while hiking. Often, the attachment buckle on a sternum strap will have a built-in whistle, perfect for reaching in an emergency situation.

Compression straps: located on the sides of a pack, compression straps are used to bring a load closer to the pack frame and can be used to secure gear on the outside of a pack.

Hydration sleeve: for carrying water reservoirs, often in a pocket that separates it from the main compartment.

Pockets: the number of pockets on a pack varies greatly. Some offer multiple external pockets with zippered access for additional gear storage and organization. Stretchy side pockets are common on most packs, handy for holding water bottles, tent poles, and other items that don’t fit as well inside a pack.
A large front mesh pocket is useful for stashing wet gear.

Shoulder strap pouch: while not included on most backpacks, you may consider purchasing a pouch that attaches to the shoulder straps for holding items that don’t fit in hip belt pockets, for example: a smartphone, sunglasses, or a compass.

External straps: on the outside bottom of a pack, useful for attaching bulky items like sleeping pads or tents.

Additional attachments: loops and tie-outs for attaching trekking poles, ice axes and/or rope.

Rain Protection

Very few backpacks are completely waterproof, so to protect the gear inside your backpack from getting wet, invest in a pack cover and/or use a heavy duty plastic bag to line the inside of your pack. A trash compactor bag works well for a liner since it is more durable than typical garbage bags and can stand up to being repeatedly stuffed with gear. 

For extra protection, especially if there is rain in the forecast, you may want to store your sleeping bag, clothing, and electronics in waterproof stuff sacks.

My Backpack & Rain Protection Gear

Osprey Aura AG 50 backpack

backpack: Osprey Aura 50 AG, small (58 oz) with top lid removed

I’ve always used Osprey backpacks, progressing from the Osprey Aura 65 to the Osprey Aura AG (anti-gravity) 65 in the first year. After replacing some of my gear with ultralight items and learning to take less gear overall, I downsized to the Osprey Aura AG 50 liter pack. This smaller pack has plenty of space for all of my gear without needing to strap things on the outside (unless I need to take a bear canister, then I carry my tent on the outside). If I need extra capacity, I use the lid, otherwise, I remove it from the pack to save weight.

The Osprey Aura is a heavily padded pack with a suspension system that hugs your body. In other words, supremely comfortable. The shoulder straps are thick and cushy to prevent rubbing on my arms and shoulders. The hip belt is constructed with mesh that connects it directly to the lumbar support and transfers the weight of the load to my hips instead of pulling on my shoulders. Overall, I find that the way the pack carries the load provides me with more stability on the trail without moving around on my back.

While I would like to be able to use a backpack that weighs less, I’ve tried several ultralight backpacks but find that the comfort of this pack is worth every ounce that it weighs. It doesn’t do much good to have a pack that weighs less if it is too uncomfortable to carry what you take.

Rain protection for my backpack

I use two methods for keeping my pack and gear dry, depending on the probability of rain in the forecast.

waterproof pack liner: Six Moon Designs pack liner (3 oz)
On every trip, I use a waterproof pack liner inside my backpack for storing my sleeping quilt, puffy jacket and clothing items. This pack liner from Six Moon Designs is a 50-liter dry bag that is seam-sealed to keep everything inside dry.

alternate pack liner: Schnozzel pump bag (3 oz)
When I’m using my Exped air mattress on trips, I use the pump sack that came with it as a waterproof stuff sack for my down gear. The Schnozzel pump sack is seam sealed with a roll-down and clasp top opening for keeping gear dry.

raincover for backpack: Osprey ultralight rain cover, large (3 oz)
When it is raining, I like using a rain cover so my pack doesn’t get wet (and heavier with water weight). Since I keep the backpack in my tent, this keeps the inside of my tent drier too. It has elastic cording to pull it tight on your pack regardless of the load or shape. I only take this on trips when there is a chance of rain in the forecast. Otherwise, I leave it at home.


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Disclosure: This post contains affiliate links for some items, which means that I make a small commission if a purchase is made. This does not change the price of the item. I am not sponsored by any gear companies and the items listed here are owned by me and are purchased with my own funds. All gear reviews are honest and not paid for by any company. Thank you for supporting this blog!