Compress Image to 20KB
ImageDrop a signature or a photo and get it back at 20 KB or less — made smaller in pixels only as far as it must be.
20 KB is what many exam and application forms allow for a scanned signature or a thumb impression, and sometimes for the photo as well. A phone picture of a signature on paper is ten or twenty times that. Drop it in and it comes back at 20 KB or less.
At this size quality alone is rarely enough, so the tool also makes the picture smaller in pixels, a step at a time, and shows the new size: measured in Chrome, a 3000 × 1400 phone photo of a signature came back at 20 KB as 2302 × 1074, and a 4032 × 3024 photo as 1124 × 843. Safari's own encoder makes larger files, so there the same pictures come back smaller in pixels — 1232 × 575 and 522 × 392 — still plenty for a form. If the form also asks for exact pixel dimensions, set those first with Smart Resizer and compress the result here. The picture never leaves your browser.
Need a different limit? Image Compressor takes any target, in KB or MB — whatever the form asks for.
Why do it here
100% private
Your image files are processed locally and never uploaded.
Instant
No upload or download wait — it runs at the speed of your device.
Free to start
Use it free every day; go Pro for unlimited runs.
No install
Works in any modern browser. No sign-up to begin.
How it works
- 1Drop the picture
A photo of your signature, or the photo the form asks for. JPG, PNG or WebP.
- 2Press Compress to 20KB
The highest quality that fits is found, and the size in pixels reduced only if it must be.
- 3Download
At 20 KB or less, with its new width and height shown if they changed.
Frequently asked questions
The form wants my signature at 140 × 60 pixels and under 20 KB — can I do both?
Yes, in two steps: make it exactly 140 × 60 with Smart Resizer, then compress that here. A picture that small is usually well under 20 KB already.
Will a 20 KB signature still look clean?
Yes, for a signature: dark strokes on plain paper keep their edges at a small size. Crop away the empty paper around it first and more of the 20 KB goes to the strokes.
Why did my picture get smaller in pixels?
Because no quality setting could fit it in 20 KB at its full size. The tool reduces the width and height a step at a time and keeps the largest that fits, and the result shows the new size.
Is 20 KB on the form 20,000 bytes?
Usually. The tool aims for 20,000 bytes, so the file passes a form that counts 20,480 as well.
Is the picture of my signature uploaded?
No. It is compressed in your own browser and saved to your device — a signature is exactly the kind of picture that should stay there.