How do I compress an image to 20 KB?

Drop your image on this page. The 20 KB target is already switched on, so the result appears straight away — then just download it. If you also need specific dimensions or a different format, turn those requirements on and they are applied in the same pass.

Will the result be exactly 20 KB?

It is guaranteed to be at or under 20 KB, never over. Landing on the figure exactly is not possible with a lossy encoder, so we always err below the limit — which is what an upload form is checking anyway.

20 KB is one of the tightest limits in common use: government exam and visa portals frequently cap the signature or photo upload here, and some older forums cap avatars at the same figure.

What if my photo cannot reach 20 KB?

Quality is lowered first; if even the lowest useful quality is still too large, the image is scaled down and the search runs again. If the target is genuinely unreachable you get the smallest result we could produce, clearly labelled, rather than a silent failure.

Is my image uploaded to a server?

No. The whole process runs in your browser using the Canvas API, off the main thread in a Web Worker. The file never leaves your device, so there is nothing for us to see, store or delete.

Compress Image to 20 KB Online — Free, No Upload

What 20 KB really means

20 KB is about the size of this paragraph repeated a few dozen times as plain text, and it is the tightest limit most people ever meet. It is common on government exam portals, older job and admission forms, and some profile-picture fields. At this size you are not trimming a photo, you are designing for a budget: every pixel has to earn its place.

A JPEG at a sensible quality spends roughly one bit per pixel on a photo of a face, a little less on a plain background. That puts 20 KB at around 150,000–250,000 pixels. A 480 × 480 image is already 230,000 pixels, which is why a 4000-pixel phone photo cannot be squeezed under 20 KB by lowering quality alone: it has to be made smaller as well.

How to get under 20 KB, step by step

Crop first. Cut away everything the form does not need: wall, sky, shoulders. Fewer pixels means every remaining pixel can keep more quality.
Drop your image on this page. The 20 KB target is already switched on, and the tool looks for the highest quality that still fits. Only if quality alone cannot get there does it reduce the dimensions and try again.
Check the result against the form. Many portals set a minimum as well as a maximum, or ask for specific dimensions. If so, turn on the dimensions requirement in the same pass instead of running the image through two tools.
Keep the original. Compress from the original file every time. Compressing an already-compressed copy loses detail twice.

What helps, what hurts

Plain backgrounds compress far better. A signature on white paper or a portrait against a flat wall can look sharp at 20 KB. A busy street cannot.
Photograph signatures in good light. Shadows and paper texture add detail the encoder then has to spend bytes on. A bright, even scan or photo is smaller and cleaner.
Use JPG, not PNG, for photos. A photographic PNG is lossless and enormous. If a PNG is all you have, convert it to JPG first.
Metadata costs space too. Camera information, GPS and an embedded preview can add tens of kilobytes. Re-encoding the image drops them, which matters when the whole budget is 20 KB.

If it still will not fit

If the image has to stay large in dimensions, such as a 600-pixel-wide photo with fine detail, 20 KB may simply be unreachable without visible damage. In that case you get the smallest result the tool could produce, clearly labelled, instead of a silent failure. Check whether the portal really means 20 KB or whether it allows a little more: the next sizes up are 50 KB and 100 KB.

Upload rules change. If a portal publishes both a size limit and required dimensions, treat the portal’s own page as the source of truth and use the figures here as a guide to what is achievable.

Why it stays on your device

Signatures, ID photos and exam forms are exactly the files you would rather not send to a stranger’s server. The compression here runs inside your browser: the file is read, shrunk and offered back for download without being uploaded anywhere. You can confirm it in your browser’s network tab: no request carries your image.