Sign PDF

How to use Sign PDF

1. Drop the PDF, then draw your signature in the pad, type it, or upload an image of one.
2. Click the page where the signature should go, then drag to resize and reposition it.
3. Add a date or initials if needed, then download the signed PDF.

Is an electronic signature legally binding?

In most cases yes, and the relevant law is clearer than people expect.

In the United States, the ESIGN Act (2000) and UETA give electronic signatures the same legal effect as ink for most transactions. In the EU, eIDAS (Regulation 910/2014) does the same and defines three tiers. In the UK, the Electronic Communications Act 2000 and the Law Commission’s 2019 statement confirm electronic signatures satisfy a statutory signature requirement.

The tiers matter for high-value documents:

This tool produces a simple electronic signature. That is sufficient for the large majority of everyday documents and is not sufficient where a qualified signature is specifically required — most commonly wills, some property transfers, and certain court and notarial documents. Those exclusions are jurisdiction-specific; check before relying on it.

What this does and does not do

It places a visible signature image onto the page. It does not apply a cryptographic digital signature — the kind that embeds a certificate, binds to a document hash, and shows a green tick in Adobe Reader.

The distinction is worth being precise about. A cryptographic signature proves two things: who signed, and that the bytes have not changed since. A visible signature proves neither on its own; it evidences intent, which is what most contract law actually requires.

If you need the cryptographic kind, you need a certificate from a trust service provider and software that can apply it. If you need an audit trail — timestamps, IP addresses, identity verification, a tamper-evident log — you need a dedicated e-signature platform, and that necessarily involves a server.

Why signing locally matters here more than anywhere

Look at what gets signed: employment contracts, tenancy agreements, settlement terms, medical consent, financial applications, NDAs about unreleased work.

Every mainstream "sign PDF online" service uploads that document to their servers. You are trusting their retention policy, their access controls, their subprocessors and their breach history with a document that, by definition, you considered important enough to sign.

This tool loads the PDF with the File API and writes the signature with pdf-lib inside the tab. Open the Network tab and sign something — no request carries the document. For anyone handling counterparty data under GDPR or UK GDPR, that removes a transfer that would otherwise need a lawful basis.

Getting a signature that looks right

Drawing with a mouse produces a wobbly line that reads as obviously mouse-drawn. Three better options:

Use a touchscreen or trackpad with a finger. The pad on this page accepts touch and pressure-independent smoothing is applied, which helps considerably.

Sign on paper and photograph it. Sign in black ink on white paper, photograph it in even light, and upload the image — the tool removes the white background automatically so it composites cleanly onto the page.

Type it. Four handwriting-style faces are included. A typed signature is perfectly valid as a simple electronic signature and is often clearer than a bad drawing.

Frequently asked questions