Compress Signature Image.
Shrink a photo of your handwritten signature to meet strict upload limits. Free, private, and instant.
Drop your photo here
or tap anywhere to choose a file
Why is the signature size limit so strict?
Application portals often set very tight limits on signature uploads — sometimes as low as 10KB to 30KB. This is because a signature is conceptually simple: dark ink on a white background. At that simplicity, very little data is needed to represent it faithfully.
A photo taken with a modern smartphone, however, is typically several megabytes. This tool compresses it down to whatever the portal requires, while keeping the ink strokes clear and legible.
Tips for a good signature photo
- Sign on plain white, unlined paper with a black or dark blue pen
- Place the paper on a flat surface in good natural light
- Photograph from directly above — avoid shadows and angles
- Crop out the margins if possible before uploading here
- A clear, high-contrast source image will compress to a smaller file with better quality
Privacy
Your signature is sensitive personal data. ToolKB compresses it entirely inside your browser — it is never sent to any server. You can verify this in your browser's Network tab (F12) during compression: there will be no outgoing file transfers.