The short answer
Take a sheet of white printer paper and sign it with a dark pen, a little larger than usual. Place the sheet on a table near a window, hold your phone flat above it and take a photo so the signature fills most of the frame. Drop the photo onto the tool below. The paper becomes transparent right away and the signature is cropped. Choose Black or Blue ink, check the preview and press Download PNG, or use Next step to place it on a PDF.
What you need for a clean result
The cleaner the original, the less the tool has to guess. Three things make the biggest difference: the pen, the paper and the light.
- Pen: a black or dark blue felt tip or gel pen gives solid, even lines. Ballpoints work too but leave lighter, broken strokes. Pencil is the hardest because it is gray and shiny.
- Paper: plain white paper without lines or a printed pattern. Lined paper leaves lines that may count as ink; if you have no other paper, the tool's Remove specks and Sensitivity settings can often hide them.
- Light: daylight from a window, without direct sun. Avoid the phone's flash, which creates a bright spot and a dark ring. Make sure the shadow of your phone and hand does not fall on the signature.
- Angle: from straight above. A slanted photo makes the signature look narrower at one side.
- Size: sign larger than usual and get close. A signature that covers half of the photo has many more pixels and looks sharper when it is scaled down on a document.
Try it here: Transparent Signature Maker
Open the full tool pageHow the tool separates ink from paper
A simple approach would say that every pixel darker than a fixed gray is ink. That fails on real photos: paper in the shade of your hand is darker than paper in the light, so one corner turns into a gray blob. The tool instead compares each pixel with the average brightness of its surroundings. Ink is much darker than the paper right next to it, whether that paper is bright or in shadow, so the signature comes out clean even with uneven light.
After that, small isolated dots such as dust, paper fibers or noise are removed, and dark areas touching the edge of the photo, usually the table or the border of the sheet, are ignored. The remaining ink is cropped with a small margin. Edges stay smooth because faint edge pixels become partly transparent instead of being cut hard.
Settings that fix common problems
Straighten looks for the angle at which the lines of writing are most level and rotates the signature by that amount; the angle is shown under the preview. A long underline has a strong influence on that angle. If your signature is meant to rise to the right and Straighten flattens it too much, turn Straighten off.
Ink color: Black and Blue repaint the whole signature in one even color, which looks crisp on printed and digital documents. Original keeps the color of your pen, useful for a colored ink or a fountain pen look.
| What you see | Change | Direction |
|---|---|---|
| Thin or light strokes are missing | Sensitivity | Higher |
| Paper texture or gray haze appears | Sensitivity | Lower |
| Small dots around the signature | Remove specks | Higher |
| An i dot or a short stroke vanished | Remove specks | Lower |
| Table or sheet edge is visible | Ignore dark areas at the edges | On |
| Signature is tilted | Straighten | On |
Using the signature in a PDF
Under the preview, Next step offers two buttons. Sign a PDF with it opens Sign PDF; as soon as you open your document there, the signature is placed on the page, ready to be dragged and resized. Add it in the PDF editor opens Edit PDF, where the signature is added as an image next to text boxes, form fields and other edits. The PNG is passed between the pages inside your browser and never uploaded.
You can also download the PNG and insert it in Word, Google Docs, Pages or an email signature. Because the background is transparent, it sits naturally on lines, colored headers and stamps. Keep the file somewhere private, like you would keep a stamp.
Is an image signature legally valid?
A picture of your handwritten signature is a simple electronic signature. For many everyday documents, such as an offer, a delivery note, a permission slip or an internal form, it is commonly accepted, because what counts is that you agreed and can be identified. For some documents the law requires more: notarized contracts, certain financial and real estate documents, or official applications may require a qualified electronic signature issued by a certified provider, or a wet ink signature on paper.
If you are unsure, ask the person or organization that asked for your signature which form they accept. This tool only creates the image; it does not add a certificate or a cryptographic signature to your PDF.