How to Digitally Sign a PDF Free — PDF Signer Guide (2026)

Whether your client said 'please digitally sign this PDF' or your HR team sent a form that needs a 'digital signature', the solution is simpler than you think — and it's free.

Electronic Signature vs Digital Signature: What's the Difference?

These terms are used interchangeably in everyday life, but technically they mean different things:

• Electronic signature — a visual mark (drawn, typed, or image) placed on a PDF to indicate your intent to sign. Legally valid under the ESIGN Act and eIDAS.
• Digital signature — a cryptographic certificate attached to a document that mathematically proves identity and detects tampering. Required for highly regulated industries.
• For 99% of everyday use cases (contracts, NDAs, HR forms, rental agreements) — an electronic signature is what people mean when they say 'digitally sign'.

How to Digitally Sign a PDF Free (Step by Step)

1. 1Open signpdf.top/sign in your browser
2. 2Upload your PDF (your file stays local — it is never sent to a server)
3. 3Click 'Add Signature'
4. 4Draw your signature with your mouse or finger, or type your name
5. 5Position the signature on the document
6. 6Click 'Download PDF' — done

Best Free PDF Signers in 2026

• Signpdf — browser-based, no upload, no account required. Best for privacy.
• Smallpdf — cloud-based, easy to use, daily free limit
• iLovePDF — cloud-based, good for batch processing
• Mac Preview — built-in on macOS, works offline
• Adobe Acrobat Reader — free reader with basic signing, account required

Is a Digitally Signed PDF Legally Binding?

Yes, in most cases. Electronic signatures created with a PDF signer are legally recognized under U.S. federal law (ESIGN Act) and EU law (eIDAS). They're valid for employment contracts, business agreements, NDAs, lease agreements, and more.

The only cases where a simple electronic signature may not be sufficient: wills, court orders, and some real estate transactions that require a notary.