QuickMergeHow to Add a Signature to a PDF
Draw your signature, type it, or upload a PNG of one — then click the page to place it, drag to size it, and download the signed PDF. The document is rendered and rewritten inside this browser tab, so the signed file is never uploaded anywhere.
How do I sign a PDF?
Sign with a mouse, a trackpad or a finger. The blank margin is trimmed automatically so the signature sits on the line.
A PNG with a transparent background gives the cleanest result. A photo of a signature on white paper works, but the white rectangle comes with it.
Drag a signature image here
or click to browse — PNG, JPG or WebP
Your signature:
Drag the PDF you want to sign here
or click to browse — the pages render below and you click to place the signature
No signature placed yet.
What this produces: an electronic signature — an image of your signature stamped onto the page. That is what almost every form asking you to “sign and return” means, and it is legally recognised for most agreements. It is not a cryptographic digital signature backed by a certificate. The difference is explained below.
How to add a signature to a PDF in your browser
Signing a PDF used to mean printing it, signing the paper, scanning it back and emailing a crooked photograph of your own document. The whole detour exists because the signature has to be your handwriting, and for a long time the only way to get handwriting into a file was through a scanner. It is no longer necessary. A signature is an image, a PDF page can hold an image, and both halves of that run perfectly well inside a browser tab.
There are three routes above and they suit different situations. Drawing gives the most authentic result and is genuinely good on a phone or tablet, where a finger or stylus produces something close to your real signature. Typing is fastest and is what most people actually want when a form says “sign here” on a routine document — it is a rendered name in a script face, and it counts as an electronic signature exactly as a drawn one does. Uploading is the right choice if you already have a clean PNG of your signature, which is worth making once and reusing.
Step by step
- Create the signature. Pick Draw, Type or Upload above and confirm it with “Use this signature”. It appears under the tabs so you can see what you are about to place.
- Load the PDF. Drop it into the second box. Every page renders below, so you can scroll to the signature block rather than guessing at a page number.
- Click where it goes. The signature lands where you clicked. Drag it to nudge it onto the line, and drag the small square at its corner to resize — the aspect ratio is held so it cannot end up stretched.
- Add more if the document needs them. Contracts frequently want initials on every page or a signature in two places. Click again on any page; each placement is independent.
- Apply and download. The signature is drawn into the page content and the file downloads as
signed.pdf.
The signature becomes part of the page
When you apply it, the image is written into the page itself rather than added as an annotation or a form field. That is deliberate, and it is the behaviour you want for a document you are sending back. An annotation can be selected and deleted in any reader, and some readers do not print annotations at all — which is how people end up mailing a signature page that arrives blank. A stamped image prints and displays the same everywhere, because to every other program it is simply part of the page.
The trade is that it cannot be moved afterwards. Get the position right before you download; if it lands badly, remove it with the button above and place it again rather than re-editing the finished file.
Electronic signature or digital signature? They are not the same thing
These two terms are used interchangeably in ordinary speech and they mean genuinely different things. The distinction matters because a form occasionally demands one specifically, and because tools that offer one are frequently described as offering the other.
An electronic signature is any mark applied to a document electronically with the intent to sign: a drawn signature, a typed name, a scanned image, sometimes a tick box. Its legal force comes from that intent plus whatever evidence exists that you were the one who signed. This is what the tool above produces, and it is what the overwhelming majority of documents mean when they ask you to sign — employment paperwork, tenancy agreements, consent forms, invoices, school and NHS forms.
A digital signature is a specific cryptographic operation. A certificate issued to you by a certificate authority contains a private key; signing computes a hash of the document and encrypts that hash with the key. Anyone can verify it with your public certificate, and because the hash covers the file's bytes, any later change to the document breaks the signature and the reader says so. It proves two things an electronic signature does not: who signed, verified by a third party, and that not one byte has changed since.
The practical rule: if a document asks for a signature, an electronic signature is what is wanted. If it asks for a digital certificate, a qualified electronic signature, or says the signature must be “verifiable” or “certificate-based” — common in government filings, some regulated financial submissions and certain court documents — you need a certificate from a certificate authority, and no browser tool can issue you one. The full explanation of how digital signatures and PKI certificates work, including where each is legally required, is in the guide.
This page describes how the technologies differ. It is general information, not legal advice, and the requirements for a specific document in your jurisdiction are a question for a qualified professional.
Why signing in the browser matters more than for most tools
Every tool on this site runs on your device, and on most of them that is a privacy preference. Here it is closer to a requirement. The documents people sign are the most sensitive files they handle: contracts, offer letters, tenancy agreements, medical consent forms, powers of attorney. A signed copy carries both the content and an image of your handwritten signature — the two things you would least like sitting in a third party's storage bucket.
The pages are rendered with pdf.js and the signed file is written with pdf-lib, both loaded into this tab and both running against memory here. There is no upload step, no account, no processing queue and no copy of your document or your signature on any server, because there is no server involved in the work. You can confirm that yourself — open your browser's network panel, sign a document, and watch that nothing carrying the file is sent. The repeatable version of that check is written up separately.
After signing
If the document also needs fields other people will fill in, build it as a form with the fillable PDF tool before signing rather than after. If you need to add dates, reference numbers or text alongside the signature, type directly onto the PDF. If the signed document is confidential, add a password as the final step — after signing, since encrypting first makes the file unreadable to every other tool here. And if you are signing something that arrived as a Word file, converting it to PDF and signing that is usually less trouble than fighting Word's signature line.
Frequently asked questions
Create a signature above — draw it, type your name, or upload a PNG — then load your PDF and click where the signature should sit. Drag to position it, drag the corner to resize, then choose Apply and download. Everything happens in this browser tab and the signed file is not uploaded.
Use the tool on this page. The PDF is rendered with pdf.js and rewritten with pdf-lib, both running inside your browser, so the document and your signature stay on your device. There is no account, no watermark and no upload step.
In most jurisdictions an electronic signature — a mark applied with the intent to sign — is legally recognised for the majority of everyday agreements. That is what this tool produces. Some documents specifically require a certificate-based digital signature instead, and that is a different technology. This is general information rather than legal advice.
An electronic signature is any mark applied with intent to sign, such as a drawn or typed name. A digital signature is a cryptographic operation using a certificate issued by a certificate authority, which proves who signed and that the file has not changed since. The guide explains both in full.
Yes, and drawing is noticeably better there than on a desktop. The signature pad accepts touch and stylus input, so a finger or an Apple Pencil produces something much closer to your real signature than a mouse does.
Not easily, and that is intentional. The image is drawn into the page content rather than added as an annotation, so it prints and displays identically in every reader. Annotations, by contrast, can be deleted in any viewer and some readers do not print them at all.
Yes. Every page renders below the tool, and clicking any of them places another copy. Contracts that want initials on each page as well as a signature at the end are handled in one pass.
No. Drawing it with a mouse, trackpad or finger avoids the scanner entirely. If you already have a scanned signature, upload it — a PNG with a transparent background sits on the line most cleanly, while a photo on white paper brings its white rectangle with it.