Compress image to 10 KB

Ten kilobytes is a pixel problem

A 10 KB limit is the smallest you'll commonly meet, and it is set for small things: a signature, a left thumb impression, sometimes a stamp-sized photo. Drop the image above — the target is already 10 KB. If it fits, you just download. If it doesn't, the reason is almost always pixels, not quality.

What fits in 10 KB

Think of it as a budget of about 10,000 bytes. A signature of around 140 × 60 pixels needs only a small part of that, even at high quality. A small passport-style photo of about 200 × 230 pixels can also fit, though with less detail to spare. A full phone photo at 3,000 or 4,000 pixels wide cannot fit at any quality — squeezing it that far only produces blocks. So we lower the pixel size first, to something sensible for your target, and then use the best quality that fits. If your form names exact pixels, enter them under Exact size and more options so the result matches the form, not our guess.

PNG screenshots and white space

Two hidden size traps: PNG files and big empty margins. A signature saved as a PNG screenshot can be ten times larger than the same signature as a JPG — we save JPG, which most forms ask for anyway. And a signature in the middle of a whole A4 photo wastes the budget on blank paper. Crop to the ink, or let the signature maker do it: it whitens the paper, removes shadows and trims to the signature before hitting your KB range. For thumbprints, the thumb impression maker does the same for ink blobs.

When the form also has a minimum

Some forms say "between 4 KB and 10 KB". Very clean images can come out under the minimum and get rejected for being too small. Put the minimum in under more options and we keep the file inside the range without changing what it looks like.

Private by design

Your signature is the most personal image you'll ever upload. Here it never leaves your phone or computer: compression runs in your browser, and nothing is sent to a server.