How to Choose Your Backpack Capacity Based on Trip Length

Choosing the right pack is intimidating. There are so many types, so many options, all sorts of technical aspects that even reading a single tag can throw you into a spiral of gear-induced anxiety.

Find out which pack size is best for your trip. Photo: Lukas Robertson/Unsplash

Embarking on a backpacking trip soon? The length of your trip will determine how big of a pack you’ll need – depending on which supplies you deem necessary.

The formula for choosing the correct pack capacity for your next trip is simple, and varies slightly depending on who you ask, but at the end of the day, comes down to personal preference. For example, if you’re a light packer and have all of the necessities you’ll need for a week in the wild, you may not necessarily need an 80 liter pack.

If you’re willing to carry extra weight and want more “comforts” on a trip, by all means size up, but please, don’t complain about the weight.

Here’s a quick guideline on how to pick the appropriate pack size for your next backpacking trip.

Weekend Trip: 1-3 nights = 30-50 liters

Packing light has its benefits, if you can forgo a few luxuries. Photo: Lionello Delpiccolo/Unsplash

Because modern packs have really cut down on weight, if you’re going on a quick trip, with a little self-discipline and planning, you can pack quite lightly.

Keep in mind what you really need. This might mean leaving the pack of cards, the camp pillow, and the wine at home, but if you’re only gone for a few days, you most likely won’t miss these small luxuries.

If you’re looking for a 30-50 liter pack, we recommend the Osprey Stratos 36 ($170). It’s lightweight enough for a day trip, with adjustable torso lengths and ventilation to keep you cool and comfortable on the trail.

Multiple Day Trip: 3-5 nights = 50-80 liters

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More time out in the wild requires more food and water, obviously. If you’re going on a warm-weather trip, you won’t have to worry about stuffing extra layers or supplies in here – just what you’ll need to keep yourself fed and hydrated.

Research says we should drink at least 2 liters of water a day – and that’s not counting the miles you’re hiking to get to your destination on your backpacking trip. Carry at least 2 liters with you at a time, as well as a filter in case water sources aren’t confirmed to be safe.

A top-rated 3-5 day pack is the Osprey Aether AG 60 ($290). Meant for carrying heavy loads for multiple days on the trail, the Aether AG 60 is a robust pack that also features a convertible top lid that can be turned into a day pack.

Extended Trip: 5+ nights = 70 liters and up

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Even longer trips mean even more supplies. You’ll want a larger pack for anything more than five nights, so that you can fit extra layers, warmer gear, and again, food and water.

If you’re a family and will need to end up carrying kids’ gear, it’s also a good time to consider sizing up a pack to accommodate their supplies as well.

The Granite Gear Nimbus Trace Access 70 ($350) is a top-rated pack that is big enough to keep you well-supplied on extended missions, with plenty of entry points for easy gear access and an adjustable torso length and swap-able shoulder pads and hip belts for men and women.

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