Signature background remover (transparent PNG)
Turn a photo or scan of your handwritten signature into a clean transparent PNG for documents, PDFs and online forms, in black, blue or the original ink colour.
Input
How to use this tool
- Enter your values or choose a local file. Replace the example data with your own.
- Review options, units and assumptions, then run the tool.
- Check the result before copying or downloading it. Keep an original copy of important files.
Method & assumptions
Turn a photo or scan of your handwritten signature into a clean transparent PNG for documents, PDFs and online forms, in black, blue or the original ink colour.
Otsu threshold on brightness → soft alpha ramp → ink recoloured → trimmed to the signatureWorked example
signature-photo.jpg (2400 × 1100) → signature.png (transparent, trimmed, black ink)
Limits & important notes
Works best with dark ink on plain white paper in even light. Shadows from your phone can be mistaken for ink: lower the sensitivity if grey patches remain. Use your signature only where you are allowed to sign.
Content updated:
Privacy & Free to use
Are my inputs stored?
Your inputs stay in this tab. We do not receive your files, pasted text or calculation values.
Is this tool free?
Yes. No signup or payment is required.
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