Sign PDF
This tool adds a handwritten signature to a PDF without sending the file anywhere. Draw your signature with a mouse, trackpad, finger or stylus, pick the page and one of five positions, then download the signed copy. Signatures you draw are kept in a small local library in your browser, so the next document only takes a few clicks.
100% in your browser. Your file never leaves your device.
Features
- Draw your signature with a mouse, trackpad, finger or stylus on any device.
- Save up to 20 signatures in your browser and reuse them on later documents.
- Place the signature on any page of the document, in a corner or centered.
- The ink is cropped and embedded as a transparent PNG — no white box behind it.
- The PDF is processed entirely in your browser and is never uploaded.
- The signed copy downloads as a new file; your original stays untouched.
About this tool
The signature pad is a plain HTML canvas that listens to pointer events, so it works the same with a mouse, a trackpad, a touchscreen or a pen. When you save, the tool trims the empty space around your strokes and stores the result as a transparent PNG in your browser's localStorage — a small library that holds up to 20 signatures.
The actual signing is done by pdf-lib, an open-source JavaScript library that runs right on the page. Your PDF is read into memory, the PNG is embedded, and the image is drawn at the chosen anchor: its width is 30 percent of the page width, capped at 180 points, the height follows the drawing pad's fixed proportions, and a small margin keeps it off the edges.
Nothing is transmitted at any point: the file is opened with the browser's file API, modified in memory and saved back to your device with a -signed suffix. Keep in mind that the result is a visual signature — an image printed onto the page — not a cryptographic digital signature with a certificate. For qualified signatures you need a dedicated trust service.
How to sign a PDF
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Drop your PDF into the tool
Drag the PDF onto the dropzone or click the select button to pick it from your device. The file is opened directly in the browser — there is no upload step and no waiting for a server.
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Pick a signature or draw one
A picker shows every signature saved in this browser. Choose one, or click the plus tile to open the drawing pad and sign with your mouse, finger or stylus. You can name the signature and clear the canvas to retry.
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Choose page and position
Enter the page number that should carry the signature and pick one of five anchors: bottom right, bottom left, top right, top left or centered. A preview shows the signature you selected.
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Sign and download
Click the sign and download button. pdf-lib embeds the signature image into the page and generates a new file named after the original with a -signed suffix, which downloads straight to your device.
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Reuse your signature next time
Your signature stays in the local library, so the next document is just drop, pick, download. Signatures can be deleted from the picker at any time, and the same library is available in the PDF viewer.
Typical use cases
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Signing a contract from email
A rental agreement or job contract arrives as a PDF and needs to go back the same day. Instead of printing, signing and scanning, drop the file here, draw your signature once, place it bottom right on the signature page and email the downloaded copy back — the whole round trip takes about a minute.
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Recurring freelance paperwork
Quotes, order confirmations and NDAs tend to arrive in a steady stream when you are self-employed. Because the tool keeps your drawn signature in a local library, each new document only needs three clicks: drop, pick the saved signature, download. No account is needed, and confidential client files never leave your machine.
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Forms signed on a tablet
School permission slips, insurance forms or club registrations often just need a signature at the bottom of the last page. On a tablet or phone the pad reacts to your finger or a pen, so you can sign naturally on the screen and send the finished PDF on without ever touching a printer.
Tips & limitations
- The result is a picture of your signature on the page, not a certificate-based digital signature. It does not make the PDF tamper-proof, and the image could in principle be copied.
- Placement is limited to five fixed anchors, and the size is set automatically to roughly a third of the page width. For free positioning and resizing, open the file in the PDF viewer instead.
- Draw large and use the full width of the pad — the tool trims the empty margin afterwards, and wide, sweeping strokes look much cleaner in the PDF than tiny ones.
- Saved signatures live only in this browser's storage. They do not sync to other devices, and clearing site data deletes them — you will simply have to draw a new one.
Frequently asked questions
Is a drawn signature legally valid?
In many everyday situations, yes: a drawn signature counts as a simple electronic signature, which the EU eIDAS regulation and similar laws elsewhere recognize for most informal agreements. It is not a qualified electronic signature (QES), so contracts that legally require written form or strong proof of identity still need a certified signing service.
Is my PDF uploaded to a server?
No. The file is opened with the browser's file API and processed by pdf-lib, a JavaScript library running on your device. The signed copy is generated locally and downloaded directly — the document never travels over the network, which also makes the tool suitable for sensitive contracts.
Can I save my signature for later?
Yes. Every signature you draw is stored in your browser's localStorage, up to 20 of them, and appears in the picker the next time you sign — here and in the PDF viewer. The library is tied to this browser on this device; other devices will not see it.
Can I sign several pages in one go?
Not in one pass — the tool places one signature on one page per run. If you need initials on every page, sign the document, then drop the downloaded copy back in and repeat, or use the PDF viewer, where you can place several signatures freely before downloading.
Can I upload a photo of my signature instead of drawing it?
No, this tool only accepts signatures drawn on the pad. Uploading an image file as a signature is not supported in the browser version. Drawing with a stylus or a finger on a touchscreen usually gets very close to your paper signature.
Does it work with password-protected PDFs?
Sometimes. The tool asks pdf-lib to ignore encryption when opening the file, which succeeds for some protected documents, but files with strong encryption or strict permissions can still fail with an error message. In that case, remove the protection first — for example in the program that was used to protect the PDF.
Can I change the size or exact position of the signature?
Not here: the size is calculated automatically — about 30 percent of the page width, at most 180 points — and the position snaps to one of five anchors with a fixed margin. If you need pixel-precise placement or a different size, place the signature in the PDF viewer, where it can be dragged and resized.
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