Compress Image to 20KB
Get any photo under 20 KB - the standard cap for signature uploads on exam and job portals.
The Most Common Signature Size on the Web
20 KB is the number that appears most often next to a signature upload box, and it is a comfortable one to hit. A scanned signature on white paper compresses to 20 KB with room to spare, and even a small headshot can make it if you accept some softening. The compressor searches for the highest quality that still fits under 20,480 bytes rather than guessing at a fixed quality, so you get the best-looking file that the limit allows. Everything runs on canvas in your own browser, which matters when the thing you are compressing is your actual signature.
How to Compress an Image
Upload your image
Pick a JPG, PNG, WebP, or GIF file from your device. It stays on your computer - nothing is sent to a server.
Set a target size or quality
Type the exact KB size a form or upload limit requires, tap one of the presets, or switch to the quality slider for manual control.
Download the compressed file
Check the before and after sizes, then save the smaller image in JPG, PNG, or WebP.
Where a 20 KB Limit Shows Up
- Signature fields on university and competitive exam applications
- Job portal profiles that cap the signature at 20 KB
- Bank and KYC forms asking for a scanned specimen signature
- Small identity photos on legacy government portals
- Attachments for ticketing systems with tight per-file limits
- Any form that rejects your upload with "file too large"
Compressing to 20 KB
Is 20 KB enough for a signature scan?
Comfortably. A signature is mostly white space with a few dark strokes, which is exactly the kind of image JPEG compresses well. It usually lands under 20 KB with quality to spare.
Can I compress a passport photo to 20 KB?
You can, but faces need more data than signatures. If the form allows 50 KB or 100 KB for the photo, use those instead and keep 20 KB for the signature.
Does the result stay a JPG?
Yes, JPG is preselected because it hits small targets best. You can switch to PNG or WebP if the form requires it.
Is my signature uploaded anywhere?
No. The compression happens entirely in your browser, so the scan never leaves your device.
Related tools
Compress Image to 10KB
Squeeze a photo down to a 10 KB JPG - the size scanned signatures and thumb impressions are usually capped at.
Compress Image to 50KB
Reduce a photo to 50 KB or less - the most common cap for passport-style photos on application forms.
Resize Signature
Get a scanned signature down to the small, wide dimensions upload forms expect.