What size backpack do you need?
Too small and your gear will not fit, too big and you will fill it with things you do not need. Match the pack to the trip, in liters.
Look for about
a 45 to 55 L pack works for this trip
That puts you in multi-day pack territory. Size to your gear, not the other way around, and leave a little room rather than buying too big.
Backpack size by trip length
Typical volumes for 3-season trips with an average kit. Go smaller if you pack light, larger for winter or if you carry comfort items.
| Trip | Pack size | Class |
|---|---|---|
| Day hike | 15 to 30 L | Daypack |
| Overnight (1 night) | 35 to 45 L | Overnight pack |
| Weekend (2 to 3 nights) | 45 to 55 L | Overnight pack |
| Multi-day (4 to 6 nights) | 60 to 70 L | Multi-day pack |
| Extended (7+ nights) | 70 L and up | Expedition pack |
Flying with it? Check it against the airline carry-on limits first. See also how we research and rate.
The picks at the two common answers
Most results land in one of two bands. If you came out under 30 liters, the Osprey Talon 22 is our best-overall daypack. If you came out at 50 liters or more, the Gregory Paragon 58 is our best-value multi-day pack. See all pack picks →
OSPREY
Osprey Talon 22
- Volume
- 22 L
- Weight
- 2 lb 1 oz (945 g)
- Back Panel
- AirScape foam with ventilation channels
- Hipbelt Pockets
- 2 zippered
- Hydration
- Compatible up to 3 L reservoir (sold separately)
- Warranty
- All Mighty Guarantee (lifetime repair or replace)
The Talon 22 is the daypack you see on the trail more than any other for good reason: it packs in a padded hipbelt, adjustable torso harness, and dual hipbelt pockets into a 22-liter package that handles loads up to 20 lb without complaint. Owners across hundreds of Amazon ratings consistently cite its adjustability and durability as standouts.
GREGORY
Gregory Paragon 58
- Weight
- 3 lb 8 oz
- Capacity
- 58L
- Torso fit
- S/M: 15–19 in, M/L: 18–22 in
- Back system
- FreeFloat Hybrid: 7075 aluminum chassis, ventilated foam back panel
- Hip belt
- Fully adjustable FreeFloat dynamic comfort cradle
- Rain cover
- Included (stored in dedicated zippered pocket)
At under 3.5 lb with a FreeFloat Hybrid suspension that scores well for comfort on multi-day loads, the Paragon 58 sits at a rare intersection of light weight, genuine load transfer, and mid-range pricing. A full-length side-loading zipper and included rain cover add convenience features usually reserved for heavier, pricier packs. Note: the Paragon 58 is now on closeout as Gregory transitions to the updated Paragon 60 line, which makes remaining stock an even stronger value buy.
Researched, not personally tested: picks come from specs, verified-owner reviews, and expert sources, scored into the Kit Score. As an Amazon Associate I earn from qualifying purchases. We may earn a commission from links here, at no extra cost to you. How we research →
Frequently asked questions
What size backpack do I need for a day hike?
A day hike usually needs 15 to 30 liters. Around 20 L carries water, snacks, a layer, and the ten essentials, while 30 L or more suits big-mileage days, winter layers, or carrying gear for others.
Is a 40L backpack big enough for a weekend?
For a light, warm-weather overnight or weekend, 40 L can work if you pack carefully. Most people are more comfortable with 45 to 55 L for two to three nights once a sleeping bag, pad, food, and a tent go in.
What does L (liters) mean on a backpack?
Liters measure a pack's internal volume, not its weight. A 50 L pack holds 50 liters of gear. Higher liters mean more capacity, which is why trip length and season, not just personal preference, drive the right number.
What size pack for 3 to 5 day backpacking?
Plan on roughly 50 to 70 liters for multi-day backpacking. The exact number depends on how bulky your sleep system is, whether you carry winter layers, and how much food you need between resupplies.
Can I use a backpacking pack for travel?
Yes, and for one-bag travel a 35 to 45 L pack is the sweet spot: large enough for a week of clothes, small enough to carry on most airlines. Check the carry-on size limit for your airline before you fly.
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