Clean Up a Scanned Signature

What 'cleaning' a signature means

A signature captured with a phone or a scanner carries baggage: grey or yellowish paper, shadows, uneven lighting, and pale pen strokes. Cleaning it means stripping all of that away so you're left with crisp dark ink on a transparent (or clean white) background.

This tool does three things at once: it keys out the paper by brightness, deepens the ink with a contrast curve so faint strokes read clearly, and can recolour the ink to a solid black or blue. Then it trims the empty margins so the signature is ready to drop into a document or form.

How to clean a signature

1. Open your signature. Drag a photo or scan onto the tool, choose a file, or paste it.
2. Remove the paper. Adjust the background threshold until only the ink remains.
3. Sharpen the ink. Use the ink-boost slider for faint strokes, and recolour to black or blue if you like.
4. Trim and download. Auto-trim cleans up the margins; download a transparent PNG or a white-background JPG.

Start with a good capture

The cleaner the input, the cleaner the output. Sign in dark ink on white paper, fill the frame, and shoot in flat, even light. Then the threshold and ink-boost sliders only need small nudges to get a perfect result.