Photo Storage Calculator

Estimate how many photos fit on a memory card — and how much space a planned shoot will take — from your camera's megapixels and file format.

How the estimate works

File size scales roughly with megapixels: a lossless-compressed RAW file is about 1 MB per megapixel (a 24 MP camera produces ~25 MB RAWs), a fine JPEG about 0.35 MB per megapixel. Real sizes vary with ISO noise, scene detail, and bit depth, so treat results as planning estimates and keep 10–15% headroom.

Frequently asked questions

Why does my card hold fewer photos than advertised?

A “128 GB” card holds about 119 GiB after the decimal/binary difference, and the file system reserves some space. This calculator already applies a ~7% allowance.

Do higher ISO shots really take more space?

Yes — noise compresses poorly. High-ISO RAW and JPEG files are often 20–40% larger than base-ISO shots of the same scene.

How many cards should I bring to a wedding?

Wedding photographers commonly shoot 2,000–4,000 frames. Enter your planned count in the last field to see the total space needed, then double it for backup.

Last updated: 2026-07-12