Convert a Signature to Black Ink
Force a faded or off-colour signature to solid black so it survives photocopying, faxing, and low-quality printing.
Free preview · No signup · ~10 seconds
Drop a signature — image or 1-page PDF
PNG, JPG, WebP, SVG or a 1-page PDF — up to 20 MB
Runs entirely in your browser. Your image is never uploaded.
What forcing a signature to black fixes
Scanners wash ink out
A scanner reading dark blue or pencil often returns something closer to grey. On screen it looks acceptable; through a photocopier or a fax it can vanish. Forcing the ink to black restores the contrast the original had on paper.
Brightness is kept
Each pixel keeps its relative darkness and takes black as its hue, so a stroke that tapered still tapers. The signature reads as handwriting rather than a stencil.
What print actually needs
Office printing and photocopying are far less forgiving than a screen. Mid-greys break up into dots or disappear entirely. Black is the one value guaranteed to survive every reproduction step between you and the filing cabinet.
Transparency survives
Only visible pixels are recoloured. A transparent signature PNG stays transparent and keeps its exact outline.
Black tone or hard threshold
This tool keeps the soft edges by mapping brightness onto black. If you want every pixel forced to either pure black or nothing at all, use the Black and White Signature tool instead — that is the harder, stencil-like result.
How to convert a signature to black ink
Upload your signature
Drop in the signature image, transparent or on paper. Scanned to PDF instead? A single-page PDF works as well — page 1 is turned into an image in your browser.
Confirm the black
The default is a near-pure black that prints cleanly. Adjust the picker if you want a softer charcoal.
Download
Take a free preview, or download the full-resolution file with one credit.
Where black ink is the safe choice
Documents that get photocopied
Stop a faded scan disappearing the second it goes through a copier.
Official forms
Meet the black-ink instruction printed at the top of most government forms.
Fax and low-quality print
Survive reproduction methods that flatten everything mid-grey into nothing.
Certificates and diplomas
Keep an authorising signature crisp on a document meant to last.
Or just ask
Describe the edit in your own words
Type what you want changed and the assistant does it on the canvas — each step lands as a layer you can reopen, so nothing it does is baked in.
No edits yet.
Frequently Asked Questions
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How to Make a Duotone Image in Figma (Building One From Blend Modes)
Figma has no duotone effect. You assemble one from a desaturated image and two blended rectangles — here is the layer stack, the order that matters, and an honest account of what it costs to maintain.
Make your signature black
Upload, force the ink to black, and download a signature that prints.