Compress JPG to 20KB
Compress JPG to 20KB online free for signatures and ID photos. Keeps the best JPG quality that fits, in your browser: your images are never uploaded.
Drag & drop images here
Everything happens in your browser: your images are never uploaded anywhere. You can also just paste (Ctrl/Cmd+V) an image or an image URL.
MonsterConvert lowers quality as little as it can to get the file at or under this size.
Resize first (optional)
Some forms ask for a pixel size as well as a file size. Set it here and the file size is fitted after resizing.
How to compress a JPG image to 20KB
Three steps, all in your browser.
Add your image
Drag and drop your JPG (or any other image), click to browse, or paste it from your clipboard.
Check the 20KB target
The target is already set to 20KB. Change it if you need a different size.
Compress and download
Click Compress and download a file at 20KB or under, with as much quality kept as possible.
When you need 20KB
20KB is the limit many application forms set for signatures and small ID or passport-style photos. At this size the image is usually a small, tightly cropped picture, so it helps to crop first and let the compressor shrink the rest.
JPG is the format upload forms ask for most, and it compresses well: MonsterConvert lowers the quality only as far as needed, and shrinks the pixel size only if that isn't enough. Images in other formats (PNG, WebP, and so on) are converted to JPG, with any transparency filled in white.
What to expect at 20KB
As a rough guide, a typical photo saved as a JPG at 20KB is about 330 x 250 px. Simple images with flat areas can hold more pixels, and very detailed ones fewer.
Tips for getting to 20KB
- Start from the original file: re-saving an already compressed JPG down to 20KB again loses more detail each time.
- Photos and gradients suit JPG. For screenshots with small text at 20KB, check the result closely, or try WebP if the site accepts it.
- If 20KB still looks too soft, crop first: fewer pixels lets the quality stay higher.
Nothing uploaded
Compression happens in your browser using WebAssembly, so your photos and documents never touch a server.
Highest quality that fits
Instead of guessing a quality setting, it searches for the best one that keeps the file at 20KB or under.
Batch friendly
Drop in several images at once and compress them all to the same size in one go.
Related tools
Get the file ready first
Compress by quality instead
Frequently asked questions
Drop your JPG image into the box above and click Compress. MonsterConvert searches for the highest quality that still keeps the file at 20KB or under, and only shrinks the pixel dimensions if the quality alone can't get there. Then download the result.
It will be 20KB or smaller, as close to it as the search can get, which keeps as much quality as possible. It won't be padded up to the exact size. If your image is already under 20KB, it is returned unchanged.
Very large or very detailed images sometimes can't get under a small target without shrinking a lot. When that happens the row tells you it got as close as it could instead of pretending it hit the target. Try cropping away unneeded parts first, or set a larger target size.
They are converted to JPG so they can reach the target size. JPG can't store transparency, so transparent areas are filled with white. The original file is never changed.
Photograph or scan it on plain white paper in good light, crop closely around it, and compress it here. A tightly cropped signature a few hundred pixels wide fits in 20KB with room to spare.
20KB is a very small budget, so some detail has to go. The compressor lowers pixel size only as much as needed. Cropping to the face or the field the form asks for keeps the useful detail sharper.
Yes. Open "Resize first (optional)" under the size controls and set a fixed width, exact dimensions, or a percentage. The image is resized first, and the file size is then fitted to 20KB.
MonsterConvert uses 1 KB = 1,000 bytes, so the result stays under the limit whether a website counts a kilobyte as 1,000 or 1,024 bytes. The size shown next to your file uses the 1,024 convention, so it can look slightly lower than 20KB.
No. The image is compressed inside your browser using WebAssembly, so it never leaves your device. That makes it safe for ID photos and other private documents.
Yes. Turn on "Keep original dimensions" under the size controls. Only the quality changes then, so the image may end up a little over 20KB if the quality floor isn't enough.