Skip to content
ToolMug

Use ↑ ↓ to move, Enter to open, Esc to close.

Online Signature Maker

Need a signature image for a contract or form? Draw it with your finger, stylus or mouse, type your name in a handwriting font, or sign on paper and upload a photo — the paper and shadows are removed and only the ink is kept. You get a transparent PNG that sits on any document without a white box, plus a white-background JPG for systems that only accept JPG.

Runs in your browser — nothing you enter is uploaded

Sign with your mouse, finger or stylus.

Signature images

Draw, type or upload your signature on the left, then click Create signature image.

The transparent PNG can go straight into Word, Google Docs or a PDF; some systems only accept JPG, so a white-background version is available too. Nothing is uploaded.

How to use

  1. Choose Draw, Type or Upload, and pick an ink color.
  2. Click Create signature image; the transparent signature appears on the right.
  3. Download the PNG for your document, or the white-background JPG if a system requires it.

Options explained

Uploading a photo
Sign on white paper with a dark pen and photograph it in even light. The paper and shadows are removed by local brightness and the ink takes the chosen color.
Auto-crop
Empty space around the signature is trimmed, leaving a small margin.
Typed signatures
Rendered with the handwriting fonts installed on your device, so the look varies between systems.

How a photo becomes a transparent signature

Uploaded photos are first reduced to at most 1,600 pixels wide. For each pixel the tool then compares its brightness with the average brightness of the surrounding area, a square window reaching 1/16 of the image’s longer side in every direction (at least 8 pixels). That is why uneven lighting and soft shadows do not leave a grey box: only pixels that are darker than their own surroundings count as ink.

darkness = (local average − pixel brightness) ÷ local average
opacity  = (darkness − 0.10) ÷ 0.25, limited to 0–1

Pixels less than 10% darker than their surroundings become fully transparent, and pixels 35% or more darker become fully opaque. In between the opacity rises smoothly, which keeps the edges of pen strokes soft. For example, a pixel of brightness 160 on paper that averages 200 is 20% darker, giving 40% opacity. All ink pixels then take the colour you chose.

The same cleaning is not needed for a drawn or typed signature, which starts out transparent. In every case the empty space around the strokes is trimmed to a 4-pixel margin.

The white JPG is made from the finished PNG by placing it on white with a border of 15% of the signature’s height on every side, saved at 95% JPEG quality. Typed signatures use the first available font from Segoe Script, Snell Roundhand, Brush Script MT, STKaiti or KaiTi and otherwise the browser’s cursive font, which is why they differ between devices.

Frequently asked questions

Is a signature image legally binding?

An image alone is just a picture. For legally binding e-signatures on important contracts, use a proper e-signature service.

How do I add it to a PDF?

Use the Sign PDF tool to place signatures, dates and text directly on a PDF.

Is my signature uploaded?

No. It is created in your browser and gone when you close the page.

Privacy

This tool runs entirely in your browser. Your files and text are processed on your device and are never uploaded to our servers.

Related tools