Electronic vs Digital Signatures: What Each One Proves

The short answer

“Electronic signature” is the broad term. It covers any electronic mark you make to show that you agree: a signature you draw on a PDF, a typed name at the end of an email, a ticked “I accept” box. A “digital signature” is one specific technology inside that category. It is a cryptographic seal, backed by a certificate, that lets anyone check who signed a file and whether the file has changed since.

So every digital signature is an electronic signature, but most electronic signatures are not digital signatures. Which one you need depends on how the other side will check it. If a person will look at the page and see that you signed, a visible signature is enough. If their software will validate the signature, you need a certificate.

What an electronic signature is

An electronic signature records intent: you saw the document and you agreed to it. In most places the law cares about that intent far more than about the tool you used. In the United States, the ESIGN Act and the state-level UETA say a signature can’t be denied legal effect just because it is electronic. In the European Union, the eIDAS Regulation says the same about using one as evidence.

The simplest form is a picture of your signature placed on the page. It looks like ink, and for everyday paperwork that is the point: the recipient can see at a glance that you signed. What it can’t do is prove anything by itself. If someone later disputes the document, the proof comes from the context around it, such as the email thread it arrived in, who sent it and when.

What a digital signature adds

A digital signature solves the proof problem with mathematics. When you sign, the software calculates a unique fingerprint of the document and locks that fingerprint with a private key that only you hold. Your certificate, issued by a certificate authority that checked who you are, is embedded in the PDF next to it.

When someone opens the file, their PDF reader recalculates the fingerprint and compares the two. That gives the recipient three things a picture can’t:

• Integrity. If a single character changed after signing, the fingerprints no longer match and the reader says so.
• Identity. The certificate names the signer and the authority that vouched for them.
• A record that is hard to deny. Only the holder of the private key could have produced that signature.

You can see the difference in Adobe Acrobat Reader. A digitally signed PDF shows a bar across the top of the window that reports whether its signatures are valid, and a Signatures panel that lists each signer. A PDF with only a visible signature shows neither.

eIDAS sorts signatures into three levels. A simple electronic signature is any of the marks described above. An advanced one must be uniquely linked to the signer, identify them and reveal later changes, which in practice means a digital signature. A qualified one adds a certificate from an approved provider and a secure signing device, and it has the same legal effect as a handwritten signature in every EU member state.

Electronic and digital signatures compared

Which one do you need?

Start with the request itself. The wording usually tells you.

• “Please sign and return.” A landlord, school, HR team or client who will read the page is asking for a visible signature. Draw or type it, place it, and send the file back.
• “Digitally sign”, “certificate”, “DSC”, “qualified signature” or “PAdES”. These all mean a certificate-based signature. Company filings with India’s Ministry of Corporate Affairs, for example, must be signed with a Digital Signature Certificate, and some EU public procedures ask for a qualified signature.
• A link from a signing service. Services such as Adobe Acrobat Sign and DocuSign collect a visible signature, keep an audit trail of who opened and signed the document, and usually seal the finished PDF with their own certificate. Sign inside the service, because it only records signatures made there.

Add a visible signature with PDF Logic

Sign PDF adds visible signatures, initials, text, dates and checkmarks. It doesn’t use certificates, verify identity or keep an audit trail, so use it for the first kind of request above.

1. Open your document. Choose one PDF, up to 50 MB. It opens in a workspace in your browser and stays on your device. If the PDF is password-protected, remove the password with Unlock PDF first.
2. Create your signature. Under Your signing tools, select Create signature and pick a tab. Type turns your name into a handwriting-style signature, Draw lets you sign with a mouse, trackpad or finger, and Upload takes a PNG or JPG of your signature up to 10 MB. Type and Draw let you choose an ink color.
3. Decide whether to save it. “Remember this signature on this device” stores it in this browser for next time. Leave it unticked on a shared or public computer.
4. Place it. Select Use signature, then click the page where it belongs. Drag it into position and resize it until it sits on the signature line without covering any text.
5. Fill in the rest. The toolbar also has Initials, Text, Date and Checkmark. If your initials go on several pages, select the field, choose Copy to other pages, and pick All other pages or enter specific ones such as 2, 4-6.
6. Export. Select Review & download. Your browser draws the signature and fields onto the pages and builds a new file, without uploading anything. Page through the preview, then select Download PDF. Your original file is left unchanged.

The exported signature is part of the page, like ink on paper. Open the downloaded file and confirm that each mark sits where you put it.

Because the signing runs on your own device, the document is not uploaded. If your browser cannot finish the job, Sign PDF offers to do it on our server and waits for your answer. Edit PDF can place the same kind of visible signature while you make other changes to the file. Our guide to browser and server processing lists which tools upload files and which don’t.

Mistakes that get signed documents rejected

• Adding a mark to a PDF that is already digitally signed. Any change after a digital signature breaks its validation, and placing a visible signature is a change. Ask the sender how they want the document countersigned.
• A signature with a gray box around it. A phone photo of a signature brings the paper’s shadows with it. Draw the signature in the tool instead, or upload the photo, crop it closely and tick Remove white background.
• Empty fields. Sign PDF won’t export while a Text or Date field is blank. Fill it in or delete it.
• Treating the signature as a lock. A visible signature doesn’t stop anyone from editing the file afterward. A password controls who can open it, but only a digital signature reveals changes.

Getting a certificate-based signature when you need one

You need two things: a digital ID and software that can sign with it.

• Adobe Acrobat Reader is free and can sign a PDF with a digital ID. Adobe’s certificate signing documentation walks through it. You can create a self-signed ID inside Acrobat, which shows that the file hasn’t changed but leaves your identity unverified until the recipient chooses to trust your certificate.
• A certificate authority issues an ID after checking who you are, often on a USB token or through a mobile app. Recipients that ask for a digital signature usually name the providers they accept.
• A signing service handles the certificate for you and is the usual choice when several people must sign in a set order.

Frequently asked questions

Is a signature I draw on a PDF legally valid?

For most everyday agreements, yes. Laws such as ESIGN in the US and eIDAS in the EU recognize electronic signatures, and what counts is that you meant to sign. Some documents, wills for example, are excluded in many places, and some recipients set a higher bar, so ask when the stakes are high.

How can I tell whether a PDF has a digital signature?

Open it in Adobe Acrobat Reader. A digitally signed file shows a signature status bar at the top and a Signatures panel with the certificate details. If all you can find is a signature-shaped image on the page, it is a visible signature.

Does Sign PDF verify who I am?

No. It places what you add onto the page. There is no identity check, certificate or audit trail.

Can a PDF carry both kinds of signature?

Yes, and many do: a visible signature on the signature line plus a digital signature sealing the whole file. Order matters. Add visible signatures, dates and page numbers first and apply the digital signature last, because any later change invalidates it.