Backpack for hiking: how to choose the right volume and fit

HikingStore |11/11, 2026

Hiker with technical backpack on a Swedish forest trail

Your backpack is with you all day, in all weathers and on all surfaces. If it fits incorrectly or is difficult to pack, it will soon be noticeable in your shoulders, hips and balance. That's why volume and fit are the two most important issues when choosing a backpack. They are linked: a bag that is too big or too small can be difficult to load evenly and feel unstable even if the carrying system fits your body.

Start with the trip you're actually going on, your back length, and the weight you'll be carrying. The brand and liter capacity can help you compare models, but they don't determine whether the pack will work for you.

Volume by tour type: start with the packing

Guidelines help you narrow down what to try. They do not replace a packing list.

Day trip: 10–30 liters. A shorter trip requires less space. Clothing for weather changes, food, water, and safety equipment still affect how much you need to bring.
Cabin hiking without a tent and kitchen: 30–50 liters. You don't have to carry a sleeping system and cooking equipment for the entire trip, but you still need space for a change of clothes, reinforcements and food.
Tented or multi-day hike: 40–80 liters. Tent, sleeping bag, sleeping mat, kitchen and food take up space. How much depends on the length of the trip, the group's structure and how compact the equipment is.

Winter often requires more volume than summer. Sleeping bags, extra clothes and more food can be both heavier and bulkier. Efficiently packed lightweight gear can reduce the space requirement, while winter gear or a larger proportion of shared gear may require more. So see the range as a starting point, not a rule.

Before you decide, lay out everything you'll be carrying and think about what you actually need to bring. Our guide to how to pack your backpack goes over placement: heavier gear close to your back, less-needed items further down, and the day's essentials within easy reach. This will help you determine the volume you need without choosing an unnecessarily large bag.

Hiking backpack with hip belt, side pockets and breathable back panel

Fit and back length: choose according to your body, not the label

Fit is more important than gender. A model marketed for women may fit a man with a shorter back length, and a model for men may fit a woman better. Bodies differ; try on the bag based on how it fits you.

Measure the length of your back from the C7 vertebra to the iliac crest. C7 is the vertebra that is usually clearly visible when you bend your head forward. Then measure down to the iliac crest, not to the waist. Many manufacturers provide a range of back lengths for each size. Compare your measurement to the size chart for the model in question – back lengths and sizing may vary between brands.

The hip measurement also matters, as the hip belt should sit securely and carry a large portion of the weight. Models designed for women often have a shorter back length and narrower, more contoured shoulder straps that take into account differences in chest and hips. However, the description on the label does not necessarily indicate how the model will fit you.

Try the bag with a packed weight, preferably around 8–12 kilos , in a store or at home. An empty backpack does not say much about how it will behave when loaded. STF's advice on backpacks for hiking also emphasizes that it is important to test with weight.

The hip belt should carry – the shoulder straps should hold the bag in place

A well-placed hip belt should rest on your hip bone, just below your iliac crest and above your glutes. It should not sit high on your waist. As a guideline, the hip belt should carry about 60–80 percent of the pack’s weight . The exact feel will vary with your body and the backpack model, but the majority of the weight should rest on your hips and legs.

The shoulder straps should fit snugly and keep the bag close to your body. Their job is to help with stability and balance, not to carry the entire load. If your shoulders are allowed to take on too much weight, they can quickly become tired or sore.

How you pack also affects carrying comfort. When heavy items are close to your spine, the pack pulls less backwards. Follow the advice in the packing method article and then check how the pack feels when you walk.

Pack organized with heavier gear placed near the back panel

Choose a carrying system based on the weight you will be carrying.

The weight of your pack determines how much support you need. For heavier loads, around 15 kilos or more, a carrying system with a frame or other stabilization is often important to transfer the weight to your hips. A lighter model with a simpler carrying system can work well with light packs, but requires careful loading and that the rest of your equipment does not become unnecessarily heavy.

So choose according to the pack weight you will actually carry, not the biggest adventure you can imagine. A sturdy pack may be justified for recurring long hikes with a tent and food, but an unnecessarily large pack for short day trips.

Winter hiking, snow and sledding or tenting often means carrying a heavier load than a summer trip. This is when support becomes especially important. In our guide to winter hiking gear, we go over how the season affects your packing.

Features to suit your everyday life on the trail

Features are useful when they solve a real need. Think about how you pack and what you want to reach without taking off the bag.

Top compartment for small items you want to find quickly.
Side pockets and water bottle storage to suit your habits.
Rain cover or another plan to keep equipment dry.
Compression straps that keep the load together when the bag is not full.
Attachment points for, for example, poles or sleeping mats.

A simple model can be easier to pack and fewer straps can reduce the risk of things getting caught. More compartments can make it easier to organize, but only if you use them. The Outdoor Promotion's long-distance hiking guide also addresses how features should be chosen according to the needs of the trip.

The weight of the bag is a trade-off

Backpacks vary greatly in empty weight. But the heaviest bag doesn't automatically feel the worst, and the lightest isn't always the most comfortable. A more stable carrying system may be worth a few extra grams if it makes a heavy load noticeably more comfortable to carry.

Choose based on pack weight and the length of your trip, not an abstract rule that everything has to be as light as possible. As we discuss inYou Don't Need the Newest , it's better to start with a real need than chasing the newest model.

Test, adjust and go for a walk

Try the backpack with the weight packed in and start by adjusting the hip belt. Then adjust the shoulder straps, sternum strap and load height straps. Walk around for a while, preferably with some stairs or a hill. Feel where the weight ends up and if the bag pulls on your shoulders or hips.

If it feels wrong, first check the back length, hip belt placement, and the balance of the pack. Heavy items far from your back or a slanted load can make even a properly fitting pack feel uncomfortable. For a step-by-step guide to packing, see the packing method article .

Winter use often requires more space and support

A pack that works well for summer day trips may be too small when you need to pack winter gear. More volume may be needed, and heavier loads place higher demands on the carrying system. Review what changes to your packing list before assuming the same backpack will work all year round. Also read our guide to winter camping for beginners .

Choose the bag you can carry comfortably

Choose a backpack based on your trip, your back length, and the actual weight you'll be carrying – not the brand or the number of liters per se. Try it packed, adjust the carrying system carefully, and go for a longer walk before you set off.

The right bag isn't the one that holds the most or weighs the least. It's the one that sits stable and comfortable enough that you stop thinking about it after the first mile.