Compress Image to 20KB

Compressing an image to 20KB, without the guesswork

This tool re-encodes your image as a JPG that weighs less than 20,000 bytes, and it does the work in your browser. Twenty kilobytes is the cap that exam forms, ID portals and signature upload boxes love to set, and it is small enough that an ordinary phone photo misses it by a wide margin. People land here right after a rejection message, usually with a deadline attached.

The tool aims under the strict reading of the cap, below 20,000 bytes. That detail matters because portals count a kilobyte two different ways, and a file saved at 20,300 bytes by a tool using the loose count gets rejected by a portal using the strict one.

How to compress an image to 20KB

1. Drop your image into the box above. JPG, PNG and WebP files all work, and several images can go in together.
2. The tool steps the JPEG quality down, checking the byte count after each pass.
3. If quality alone cannot reach the target, the pixel dimensions shrink as well. At 20KB that second step is common for phone photos.
4. Download your JPG, or the ZIP file if you dropped in a batch.
5. Check the result line for the final byte count before you go back to the form.

The catch with 20KB forms: many of them set a floor too

Read your form spec closely. A common signature spec is a band, 10 to 20 KB, which means the portal rejects files that are too small as well as files that are too big. A clean signature on white paper can honestly encode at 7KB, under the floor, and get bounced for the opposite reason people expect.

This compressor handles the ceiling. When your file also has to stay above a minimum, use the signature resizer instead. It takes the exact pixels and both ends of the KB band in one pass, and it pads a too-small JPG up inside the band without changing the picture itself.

What 20KB does to a photo

A signature, a stamp or a flat graphic barely notices 20KB. A photograph gives up more. Expect smaller pixel dimensions and softer fine detail, the weave of fabric and the edges of leaves first. Faces at form-photo size stay recognisable and clear, which is what the portal wants to see. If your cap allows it, the 50KB compressor keeps a good deal more of the original photo intact.

Re-encoding brings one side benefit. The new JPG drops the metadata your phone stored inside the original, location data included, before the file goes anywhere near a portal.

Already under 20KB? Then nothing happens

A JPG that already fits the cap is returned untouched. The tool does not re-encode files that already pass, because every re-encode costs a little quality and there is no prize for paying it twice. And when a detailed photo cannot reach 20KB without being wrecked, the tool returns the smallest clean version it can make and tells you on the result line, rather than handing back a ruined picture or a file that is still too big.

Your image never leaves your device

The whole job runs in your browser. No upload, no server copy, no account, no daily limit on how many images you can process. Exam photos and signatures are personal documents, and they stay on your machine from start to finish. The same goes for every tool in the image converters collection.