Compress image to 20KB
Quick answer
To hit 20KB — an extremely small target — use JPG or WebP and expect heavy down-scaling. image cat lowers quality and resolution together to converge on 20KB.
20KB is an aggressive target, typically demanded by old sign-up systems, forum avatars and e-signature uploads with very strict size caps. Drop an image in and image cat compresses it toward 20KB locally — nothing is uploaded.
How much quality survives at 20KB?
For an ordinary phone photo, 20KB almost always means a visible quality hit — details soften and you may see compression blocks. ID photos, flat logos and simple icons still look fine at 20KB; detailed landscapes or crowd shots will blur noticeably. If your system allows it, 50KB is usually a more comfortable compromise.
Staying as sharp as possible at 20KB
Choose JPG or WebP — not PNG, since lossless formats rarely fit in 20KB. Crop the resolution down to what you actually need first; a 200×200 avatar doesn't need a 4000-pixel source. image cat down-scales automatically, but shrinking it yourself first usually gives a cleaner result.
Frequently asked questions
A detailed photo is hard to fit in 20KB at full resolution. image cat automatically lowers resolution step by step to approach the target; if it still can't reach it, it returns the smallest best-effort result and tells you. Cropping to the size you actually need makes 20KB easier to hit.
Forum avatars, e-signatures and legacy sign-up systems with very tight caps. For printing or high-resolution display, pick a larger target such as 500KB or 1MB.
No. Compression runs locally in your browser via Canvas, so your image stays on your device and is never uploaded.
Updated · image cat team