How this works in your browser
A signature drawn on screen is captured as canvas strokes, a typed one is rendered in a handwriting typeface, and an uploaded image is read directly; all three end up as image data in your browser. pdf-lib then embeds that image into the page at the position and scale you chose and writes a new document. Because the mark is composited into the page content rather than attached as an annotation object, it does not float loose in a viewer the way a sticky note would. Nothing about the signature is retained: it exists only in the tab's memory for the session and is gone when the page closes, which is the behaviour you want for something that represents your identity.
Sign PDF vs. traditional online converters
| Feature | Sign PDF (in-browser) | Traditional online converters |
|---|---|---|
| File upload required | No - never leaves your device | Yes - file is sent to a server |
| Processing queue | None - starts instantly | Often, especially at peak times |
| Watermark on output | Never | Common on free plans |
| Usage limits | None - free, unlimited use | Often capped per day or file size |
| Works offline once loaded | Yes, for most tools | No - requires a live connection |
| Account required | No | Often, for anything beyond a trial |
How to use Sign PDF
- 1
Open the Sign PDF tool
Go to tools.slaytic.com and open the Sign PDF tool. No sign-up or account required.
- 2
Create your signature
Draw it with a mouse or finger, type your name in a handwriting font, or upload an image of an existing signature.
- 3
Place it and save
Drag the signature to the right spot on any page, resize it to fit the line, then save the signed document to your device.
Common ways to use Sign PDF
Returning a signed contract quickly
Sign and send back an agreement without printing, signing on paper, scanning and emailing it.
Approving forms remotely
Add your signature to permission slips, invoices or internal approvals from a phone or laptop.
Signing without a signature service
Complete a one-off document without creating an account with an e-signature provider or uploading it to their servers.
Frequently asked questions
Is this legally binding?
A drawn or typed electronic signature indicates intent to sign and is legally recognised in many jurisdictions under e-signature laws. However, it is a simple electronic signature rather than a cryptographic digital signature. Check the requirements of your specific jurisdiction and document type.
Is my signature saved or sent to a server?
No. The signature drawing is kept entirely in your browser tab memory and is permanently discarded when you close the page. Nothing is uploaded.
Can multiple people sign the same document?
You can sign and save, then share the file with the next person who signs using their own device and browser. Each signer adds their own signature in turn.
What is the difference between this and a digital signature?
Worth being precise about. This is an electronic signature: a visible mark showing you signed. A cryptographic digital signature additionally binds a certificate to the file so any later alteration is detectable. Electronic signatures are accepted for most everyday agreements; regulated contexts sometimes require the certificate-backed kind.
Can the signature be removed or moved afterwards?
Once saved, the signature is drawn into the page rather than attached as a movable annotation, so it does not drag around in a viewer. Someone determined and technical could still edit any PDF, which is exactly why high-value documents use certificate-based signing.
Should I sign before or after adding a password?
Sign first, then protect. An encrypted PDF has to be unlocked before it can be edited, so signing a protected file means removing the protection and reapplying it afterwards.
Does an uploaded signature image need a transparent background?
It helps. A PNG with transparency sits cleanly over the document, whereas a photo of a signature on paper brings its white background with it and may cover nearby text.