Free tool
Sign a PDF online, free
Open a PDF, add your signature and the date, and download the signed copy. It all happens in your browser: the file is never uploaded.
Runs in your browser. Your file is never uploaded.
Why use it
Private by design
The PDF is read and signed by your browser. It is never uploaded, so we never see or keep it.
No account, no watermark
Free with no sign-up, no watermark on the result and no limit on how often you use it.
Works on a phone
Sign with your finger on a touchscreen; the page is built for small screens first.
How it works
Open your PDF
Choose a PDF or drop it on the box. It opens on this page; nothing is sent to a server.
Create your signature
Draw it with a finger or mouse, type your name, or upload a picture of your handwritten signature.
Tap where it goes
Place the signature, and the date if you need it. Drag to move, use the corner to resize.
Download
Save the signed PDF. Your original file is left as it was.
When this tool is the right one
Use it when you are the person signing and you just need a signed file to send back: a form a landlord emailed you, a consent letter, a quote to accept, an agreement a client sent as a PDF. You sign your own copy and return it the way it came.
If you are the one who needs signatures from other people, this is not the tool. A signed file you produced yourself records nothing about who signed it or when; for that, request a signature through a signing workflow, which keeps an audit trail and gives everyone the final copy.
What it does to your file
The tool adds your signature and any date or text you place as part of the page content, then saves a new PDF. If the document contains fillable form fields, they are flattened so the signed copy cannot be quietly edited in a PDF reader afterwards. Your original file on your device is not changed; the signed copy downloads under a new name ending in "(signed)".
Signatures drawn on screen are smoothed and saved as a transparent image, so they sit naturally on the page whatever its background. Typed signatures are set in a script typeface. Uploaded images are scaled down before use, which keeps the signed PDF small enough to email.
Why it does not upload anything
Most online PDF signing sites upload your document to their servers, process it there and send it back. That means a copy of your contract exists, at least for a while, on a machine you know nothing about. This tool uses the same PDF engine Salsox uses to seal signed documents, but runs it inside your browser. The privacy benefit is not a policy; it is how the tool is built.
Tips for a clean result
- Place the signature over the signature line, then make it a little smaller than the box: a signature that overlaps text looks careless when printed.
- Add the date with the date mark rather than typing it by hand, so it is aligned and legible.
- For initials on every page, use Add signature to PDF, which can repeat a mark on each page in one step.
- If the PDF has boxes to fill in, Fill and sign PDF fills the form's own fields first.
To learn more about the kinds of signatures a PDF can carry, read the explainer on PDF signatures.
Frequently asked questions
Is it really free?
Yes. There is no account, no watermark and no usage limit. It costs us very little to run because your device does the work.
Is my document uploaded anywhere?
No. The PDF is opened, signed and saved by your browser. You can confirm it in your browser's developer tools: the network panel shows no upload when you sign.
Is a signature added this way legally valid?
An electronic signature is accepted for many everyday documents in most countries, but signing your own copy records nothing about who signed. When you need proof, send the document for signature so an audit trail is kept.
What size of PDF can I sign?
Up to 25 MB. Very large scanned documents may be slow on an older phone, because your device does the processing.
How do I get someone else to sign?
Use the request a signature tool, or create a free account to send up to three documents a month for signature with links, reminders and an audit trail.
Keep exploring
- Add signature to PDFAdd a signature image to a PDF, on one page or every page. Upload a PNG or JPG of your signature or draw one, position it, and download. Free and private.
- Fill and sign PDFFill in a PDF form and sign it online: complete its own fields, add text, dates and checkmarks anywhere, sign, and download. Free, private, no account.
- Request a signaturePrepare a signature request in seconds: add the PDF and the signers' emails, preview where each signature goes, then send with a free account.
- PDF signatureThe four kinds of PDF signature, what each proves, and which to use. Drawn, typed and image signatures, certificate-based digital signatures, and audit trails.
- How to sign a PDF: every method, on any deviceHow to sign a PDF on a computer, iPhone or Android, with free tools or the apps you already have, and when signing your own copy is not enough.
Need someone else's signature?
A free account sends 3 documents a month for signature. Signers need no account, and every step is recorded in an audit trail.