Home / Calculators / Trip bag size

Calculator

What size bag for your trip? Days to litres

Updated 2026-09-24. Researched from airline pages and published specifications.

Quick answerA carry-on of about 40 litres covers most trips up to a week in warm weather, or longer with laundry. Two weeks in a cold climate without laundry needs about 68 litres, a medium checked bag. Most people overpack: a week with laundry fits a carry-on.
What size bag for your trip? Days to litresTypical values, stated
Bag volume needed 30 litres
Recommended bagCarry-on suitcase or 40 L travel backpack
Days of clothing packed7
Fits a carry-on?yes

Litre ratings are interior volume; manufacturers measure differently, so treat 5 L either way as the same size.

How it works: litres = 12 L base (toiletries, shoes, tech) + days x litres per day, where days caps at 7 with laundry and litres per day is 2.5 warm or 4 cold, scaled for packing style

A 22 x 14 x 9 inch carry-on is 45 litres on the outside and holds about 38 to 42 litres inside. Carry-on travel backpacks run 35 to 45 litres.

Bags at the size this points to

Frequently asked questions

What size luggage do I need for a week?

For one week, a carry-on of about 40 litres, a 21 or 22 inch suitcase or a 40 L travel backpack, is enough for most people in warm or mild weather. Cold-weather layers push it toward 50 to 55 litres, which means a medium checked bag or a carry-on plus a well-packed personal item.

How many litres is a carry-on?

A bag at the common 22 x 14 x 9 inch limit measures about 45 litres on the outside, and hardside cases of that size hold roughly 38 to 42 litres inside once the wheel wells and handle channel are subtracted. The European 55 x 40 x 20 cm limit is 44 litres outside.

Researched, not professional advice. Airline limits and fees change; confirm with your airline before you fly.

Related