How to Choose the Right Backpack Size in Liters

Quick answer: For a daypack, 15 to 25 liters covers most single-day needs. For carry-on travel of a few days, 30 to 40 liters is the sweet spot. For longer trips or one-bag travel, 40 to 50 liters gives enough room without tipping into checked-bag territory on most airlines. Beyond that, you're usually better served by two bags than one oversized one.

Backpack listings throw around liter counts as if everyone already knows what 28L actually looks like packed. Here's what each range really means in practice.

Two backpacks with the same liter count can feel completely different once packed, depending on shape, compartment structure, and how much of that volume is usable versus lost to internal padding and dividers. Liters are a starting point for comparison, not the final answer.

This range covers a day's essentials: a light jacket, water bottle, wallet, maybe a small laptop or tablet. It's the category most people already own without thinking of it as a specific size bracket, since it covers commuting and errands as much as day trips.

This is the range that handles a long weekend to about a week, assuming reasonably light packing and access to laundry. Most true carry-on-compliant travel backpacks land in this bracket, since it maximizes what fits under most airlines' personal item or carry-on size limits.

This range supports one to two weeks without needing a laundry stop, or ongoing one-bag travel with a slightly more efficient packing approach. It's the upper edge of what most airlines still accept as carry-on, so it's worth checking specific dimension limits, not just liter count, before assuming it'll fit overhead.

At this size, you're generally looking at a checked bag rather than a carry-on, and often a fundamentally different type of pack (framed, hip-belt supported) built for sustained heavy loads rather than the streamlined design most everyday travel backpacks use.

Think in terms of days, not liters directly: roughly 5 to 7 liters per day of clothing for average packing, plus a fixed 10 to 15 liters for electronics, toiletries, and miscellaneous items regardless of trip length. That gives a rough target before comparing specific bag dimensions.

Our backpack lineup spans daypack through extended-travel sizing, each built with the same hemp knit durability and compartment structure, just scaled to how much you're actually carrying.

Is a bigger backpack always better for travel?
Not necessarily. Oversized bags encourage overpacking and are harder to carry comfortably, and many exceed airline carry-on limits, forcing a checked bag anyway.

How many liters do I need for a week-long trip?
Most people manage a week in the 30 to 40 liter range with efficient packing, assuming access to laundry partway through or a willingness to re-wear items.

Does liter capacity account for external pockets?
Usually yes, most listed capacities include all compartments and pockets, though it's worth checking a specific product's breakdown if precise organization matters to you.

• The Ultimate 8000Kicks Travel Backpack Guide
• Hemp Backpacks: What Makes Them Different
• How to Pack a Hemp Backpack for a Week-Long Trip

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