👜 Bag Capacity Calculator
Enter a bag's length, width, and height to get its volume in litres and the size class it falls into — a quick way to compare bags and judge how much each one really holds.
📐 Three Dimensions, One Volume
What is a Bag Capacity Calculator?
It turns three simple measurements into the one number that matters when you're choosing a bag: how much it holds. Give it the length, width, and height in centimetres and it computes the volume in litres — the same unit brands quote for backpacks and holdalls — then sorts the bag into a practical size band from clutch to travel weekender.
Use it to compare two satchels on paper, sanity-check a listing that doesn't state a volume, or decide whether a bag is big enough for your daily carry. Remember it's a box estimate: seams, lining, and shape mean real usable space runs a touch lower.
❓ Frequently Asked Questions
How is bag capacity in litres calculated?
It multiplies the bag's length × width × height in centimetres to get the volume in cubic centimetres, then divides by 1,000 to convert to litres (1 litre = 1,000 cm³). A 30 × 12 × 25 cm satchel, for example, works out to 9 litres.
Why is my real usable space a bit less than the number here?
This treats the bag as a simple box. In practice, seams, padded lining, curved or tapered panels, and fixed pockets all eat into the interior, so a bag's true packable volume is usually a little under its outer box volume. Treat the figure as a planning estimate.
What do the size classes mean?
Under 5 litres is Small/Clutch (evening bags, mini crossbodies); 5–15 litres is Medium/Everyday (day satchels and handbags); 15–30 litres is Large/Work (laptop totes and work satchels); and 30 litres or more is Extra Large/Travel (weekenders and holdalls).
Should I measure the bag's outside or inside?
For a capacity estimate, use the interior dimensions if you can — that's the space you actually pack. If you only have exterior measurements, subtract a centimetre or two per side to allow for the walls and lining before entering them.