Getting a clean result
The tool keeps pixels that are darker than the paper and makes everything else transparent. That makes the photo you start with matter more than any setting:
- Sign on plain white printer paper with a felt-tip or gel pen. Ballpoint strokes are thin and grey, and parts of them can disappear.
- Photograph in daylight from directly above, without your phone’s shadow on the page.
- Sign larger than usual. A signature that fills the width of the phone screen keeps smooth edges when it is shrunk onto a document.
The settings
- Corner handles: drag the four handles close around the signature. A tight crop keeps shadows and page edges out.
- Ink preset: Auto keeps any dark mark. Blue, Black or Red keeps only that colour, which helps when the signature crosses a printed line or text.
- Tolerance (10–60, default 28): raise it if grey paper or shadows remain; lower it if thin parts of the strokes break up.
- Darken strokes (0–60, default 20): deepens faint ink so it reads well when printed.
Is an image signature legally valid?
For everyday documents such as rental forms, invoices and consent letters, a pasted image is usually accepted as an electronic signature in the US, UK and EU. Some documents need more: wills, property deeds and some court and government forms require a wet-ink signature or a certified digital signature. When in doubt, ask whoever will receive the document.
Questions
Is my signature uploaded?
No. The photo is processed in your browser and isn’t stored or sent anywhere. Close the tab when you’re done.
The PNG shows a white box in my document.
Check that White background was unticked before extracting. Some older editors also flatten PNG transparency; setting the image to In front of text usually fixes that in Word.