Convert a Signature to Blue Ink
Recolour any signature to standard blue ink while keeping every stroke and pressure variation exactly as you wrote it.
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.
Why blue ink is the convention
Recolouring, not repainting
The tool reads how much ink is on the paper at each point and keeps it. The thin, faint parts of a stroke stay thin and faint, and they come out lighter and less saturated than the pressed-down core, so the signature still looks handwritten rather than traced.
Why institutions ask for blue
Blue ink on a black-and-white photocopy is instantly distinguishable from the printed form underneath, which is how a bank or notary tells an original signature from a duplicate at a glance. It is a practical convention, not a legal requirement, but plenty of organisations still ask for it.
Transparency is preserved
If you have already made the signature transparent, it stays transparent. Only the visible ink is recoloured, so the file drops onto any document unchanged in shape.
Picking the right blue
The presets are sampled from real pens — gel, ballpoint, fountain, navy, blue-black — and gel pen blue is preselected because it is what most documents are signed in. Lighter blues can wash out on a photocopy; blue-black is the safest if the page will be scanned again. If a specific shade is required, paste the exact hex into the picker.
No background removal needed
The tool reads where the paper ends and the ink begins, so a plain scan works on its own — the sheet drops away and only the strokes take the colour. If you have already cut the signature out, the transparency you made is left exactly as it is.
How to convert a signature to blue ink
Upload your signature
Drop in a signature image. A plain scan of a signed sheet works — the paper is removed for you — and a transparent PNG works too. Scanned to PDF instead? A single-page PDF works as well — page 1 is turned into an image in your browser.
Choose the blue
The default is a standard ballpoint blue. Adjust the picker if your organisation asks for a specific shade.
Download
Take a free preview, or download the full-resolution file with one credit.
Where blue ink is expected
Bank and legal forms
Meet the blue-ink requirement many institutions still specify for signed originals.
Contracts
Make the signature visibly distinct from the printed text of the agreement.
Documents that get photocopied
Blue survives copying as clearly different from the black of the form itself.
Official correspondence
Match the house convention where letters are expected to be signed in blue.
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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Turn your signature blue
Upload, pick the blue, and download the recoloured signature.