Blog / Education

Digital vs electronic signature on a PDF: what is the difference

Published 2026-09-07 · Education

Electronic signature and digital signature sound like the same thing, but they are not. Every day, contracts get rejected because someone asked for one and was sent the other. This guide explains the difference on a PDF, what each one guarantees, and which one you actually need.

What an electronic signature is

An electronic signature is any mark that shows you approved a document: a scanned signature image, a typed name, a drawn squiggle inside the PDF, or a click on an I Agree button. Its job is intent and identity at a simple level. It says your name is on this page, but by itself it does not prove who typed it, that nothing changed afterwards, or when it was signed.

What a digital signature adds

A digital signature is a technical seal that uses cryptography to make the signature verifiable. When you sign a PDF with a digital ID, the software scrambles the content into a fingerprint and locks it with a certificate. Anyone opening the file can confirm two things: the document has not been altered since signing, and the signature belongs to whoever holds that certificate. You can do the visual part with how to sign a PDF, but the cryptographic part is a digital signature.

Which one is legally valid

In many countries electronic signatures are perfectly valid for most everyday contracts, and a simple typed or drawn signature is enough. Digital signatures matter when the law demands proof of integrity, a verifiable identity, or a non-repudiable record, typically for high-value agreements, regulated industries and official filings. The practical rule: know what your recipient actually requires before you sign, because sending the wrong type means doing it again.

Test whether a signature is digital

You can often spot the difference by opening the signed PDF. A true digital signature shows a signature panel with a validity badge, typically a blue ribbon or a certificate warning if the file has been changed. An electronic signature is just part of the page, like a normal image. If a file comes back flagged as modified or unsigned after being digitally signed, it was altered after signing, which is exactly what the seal protects against.

Keep the signature permanent with flattening

Whichever signature you use, it needs to stay on the page when the file travels. Interactive signature layers can fail to render on another viewer or an email, leaving the document looking unsigned. Flattening fuses those layers into the page so the signature shows identically everywhere, a step that is essential for signed contracts you email around, as covered in the guide to flattening a signed PDF.

Protect the signed document before sharing

After signing, add a layer of control over who can alter the file. Password-protecting the PDF lets you restrict printing and editing so the approved version is the only one that circulates. If a recipient legitimately owns the password and needs a copy they can reuse, the file can be unlocked again with Unlock PDF. Between the signature and the password, the document stays exactly as you approved it.