Comparing Backpacks for Hiking | Fit And Size First

Most hikers start with the wrong question. They ask about their height, when the two numbers that actually decide a pack are your torso measurement and how many nights you plan to carry gear. Get those right and the pack carries you. Get them wrong and even a premium bag turns a ridge line into a misery. Here’s the short version: measure your torso, match it to the brand’s chart, then pick a liter range that fits your longest trip.

What Size Backpack Do You Need By Trip Length?

Capacity matters for one reason: it sets whether your gear fits without turning into a sagging, overloaded mess. The rough ranges below hold across most mainstream brands.

Academy Sports’ sizing guide puts day hiking at 30–35 liters for trips of one to ten hours, while REI’s fitting guide frames the overnight range at 20–50 liters. The ranges overlap because your gear volume matters more than the calendar. A winter overnight with a bulky sleeping bag can push you to the top of that range, and a minimalist summer trip might sit near the bottom. Choose capacity for the gear, not the trip name.

How To Measure Torso Length For A Pack

Torso length is the distance from your C7 vertebra to your iliac crest, and it is the only measurement that matters for pack fit. C7 is the prominent bump at the base of your neck, the one that sticks out when you tilt your head forward. The iliac crest is the top edge of your hip bones, running across your waist like a shelf. Measure between those two points with a flexible tape and you have your torso number.

REI’s fitting guide maps those numbers to sizes: extra small up to 15 inches, small at 16–17 inches, medium or regular at 18–19 inches, and large or tall at 20 inches and up. The Washington Trails Association gives the same advice, noting that packs are sized by torso length rather than height. Two hikers at the same height can easily wear different sizes.

How Should A Loaded Hiking Pack Sit?

When the pack is on and loaded, the hipbelt should wrap the iliac crest and carry roughly 80% of the weight. That is the consensus across fit guides, and it is the difference between a pack that works and one that fights you. The shoulder straps stabilize the load, but they should never bear the brunt of it. If your shoulders ache before your hips do, the fit is off.

To get there, follow the same sequence every time you load up. Loosen every strap. Buckle the hipbelt first and pull it snug so it sits on the crest of your hip bones. Then tighten the shoulder straps until they touch lightly. Finish with the load lifters at the top of the shoulder straps and the sternum strap across your chest. That order puts the weight where the pack was designed to carry it.

What Should You Expect To Pay?

Realistic pricing lands between $50 and $200 new, per the Washington Trails Association, and REI’s current category page shows US retail prices ranging from about $49 to $182. Weight matters too. A lighter pack is easier on the trail, but it often comes with less support, so weigh that trade against what you carry.

Before you buy, check the manufacturer’s chart for the exact model. Sizing varies by brand, and a medium in one line can feel like a large in another. When you find a pack that fits your torso and covers your longest trip, that is the one worth the money. If you plan to carry a camera alongside your trail gear, our roundup of hiking backpacks for camera gear covers tested models that protect optics without sacrificing fit.