“Just e-sign it and send it back” can mean very different things. Sometimes it means dropping a picture of your signature onto the last page. Sometimes it means a cryptographic signature backed by a certificate that proves who signed and that nothing has changed since. This guide explains the difference in plain English, so you know what you’re creating, what it proves and when it’s enough.
Not legal advice. This is a general explanation. Rules differ between countries and between types of document. If a lot rides on a signature, ask the person who asked you to sign, or a legal adviser.
Three things people call an “e-signature”
“Electronic signature” is a broad term. In everyday use it covers at least three quite different things:
- An act of agreement, such as typing your name at the bottom of an email, ticking “I agree”, or clicking a button on a website. There may be no signature image at all.
- A visual signature: an image of a signature (drawn, typed in a handwriting-style font, or photographed from paper) placed on a document. This is what most free PDF signing tools, including PDFMagpie’s Sign PDF, create.
- A certificate-based digital signature: a cryptographic seal embedded in the PDF, tied to a digital certificate that identifies the signer and reveals any later change to the file.
The first two depend on context and evidence for their weight. The third carries technical proof inside the file itself.
Visual signatures: what they are and what they show
A visual signature is exactly what it looks like: a picture. When you sign with a tool like ours, your drawn, typed or uploaded signature is placed on the page, and when you save, it is drawn permanently into the page content alongside the text. It looks like a signed paper document, and it prints like one.
What it shows is intention: someone put this mark here to indicate they agree. What it doesn’t do on its own is prove who that someone was, or that the document hasn’t been altered since. Anyone with the image could place it on another document, and anyone with an editor could change the text around it. In that respect it’s much like a signed paper copy that has been scanned: its weight comes from the surrounding evidence. That includes the email it arrived from, the conversation around it, and copies kept by both sides.
That sounds weak, but for most everyday paperwork it’s exactly what’s wanted. Landlords, schools, employers and clubs usually just need a clear record that you agreed, and a visual signature sent from your own email address provides one.
Certificate-based digital signatures
A digital signature works quite differently, using public-key cryptography:
- The signer has a digital certificate, issued by a certificate provider (sometimes called a trust service provider or certificate authority) after checking their identity to some level. The certificate contains a public key; the matching private key stays with the signer, often on a smart card, a secure device or a signing service.
- When signing, the software calculates a fingerprint (a hash) of the document and encrypts it with the private key. The result, together with the certificate, is embedded in the PDF.
- Anyone opening the file can check the signature with the public key. If even one character of the signed content has changed, the fingerprint no longer matches and the reader reports the signature as invalid.
- A trusted timestamp can be added to show when the signing happened.
So a digital signature answers two questions a visual one can’t: which certificate signed this? and has it changed since? It may or may not also show a signature image on the page. The image is decoration; the proof is in the cryptography.
The trade-off is effort and cost. The signer needs a certificate, which usually means an identity check and often a fee or an employer-provided account, plus software that can apply it. That’s why digital signatures are common in government, finance, healthcare and some cross-border business, and less common for a school trip form.
Side by side
| Visual signature | Certificate-based digital signature | |
|---|---|---|
| What it is | An image of a signature on the page | Cryptographic data embedded in the PDF, linked to a certificate |
| Identifies the signer | No, it relies on context (email, records) | Yes, through the certificate, to the level the provider checked |
| Shows later changes | No | Yes, the signature shows as invalid if signed content changes |
| What you need | A browser and a few seconds | A certificate, compatible software, often an identity check |
| Typical uses | Tenancy forms, consent slips, HR forms, everyday agreements | Regulated filings, some contracts, official and cross-border documents |
| Cost | Free | Often paid or provided by an employer or service |
What the law says, in outline
Many legal systems have a broadly similar starting point: a signature shouldn’t be rejected just because it is electronic. A few examples, simplified:
- United Kingdom: the Electronic Communications Act 2000 and the UK’s retained version of the eIDAS regulation recognise electronic signatures, and the Law Commission’s 2019 report on electronic execution concluded that an electronic signature is generally capable of validly executing a document, provided the signer intends to authenticate it and any formalities are met. Some documents have extra formalities: deeds normally need a witness, and wills in England and Wales still need to be signed and witnessed under strict rules.
- European Union: eIDAS defines three levels: simple electronic signatures, advanced electronic signatures (uniquely linked to and capable of identifying the signer, and able to detect later changes) and qualified electronic signatures, which have the same legal effect as a handwritten signature across the EU.
- United States: the federal ESIGN Act and state laws based on the Uniform Electronic Transactions Act give electronic signatures legal effect for most transactions, with exceptions such as wills and certain notices.
In practice, two questions usually decide things: does the recipient accept this kind of signature, and does this type of document have special formal requirements? Many organisations state what they accept. If they don’t, ask before you sign.
Which one do you need?
A visual signature is usually fine when:
- the person or organisation asking has said a signed PDF or scan is acceptable;
- it’s an everyday agreement: a consent form, timesheet, delivery note, booking form or simple tenancy paperwork;
- you’d otherwise print, sign by hand and scan, since a visual signature is the digital equivalent of that.
Look for something stronger when:
- the recipient asks for a “digital signature”, “qualified signature” or a specific signing platform;
- the document is a deed, a will, a lasting power of attorney, or a property transfer, all of which often carry formal requirements;
- it’s a regulated or official filing, or the value at stake is high and identity really matters;
- several parties need to sign in sequence with an audit trail. That needs a signing service that keeps records, which a browser-only tool can’t do.
How to tell what kind of signature a PDF has
Open the PDF in a full-featured desktop reader. If it contains a certificate-based signature, the reader typically shows a signature panel or banner reporting whether the signature is valid, who signed it, and whether the document has been modified since. Clicking the signature on the page usually opens those details.
If you see a signature on the page but the reader shows no signature panel or validity message, it’s a visual signature (an image or drawing). Browser-based viewers and phone apps often don’t display signature validity at all, so check on a desktop reader if it matters.
Signing well with a visual signature
If a visual signature is what’s needed, a few habits make it clearer and more useful as a record:
- Send it yourself, from your usual email address, and keep the sent message. The email trail is part of the evidence that you signed.
- Date it. Sign PDF has a Date button with day-month-year and numeric formats.
- Initial every page if asked. Place your initials once and use Copy to other pages.
- Fill in the form first. Complete fields with Edit & fill and flatten it, so values can’t be changed later in a form-filling reader.
- Keep your signature image private. Our Sign tool only remembers your signature if you tick the option, and then only in your own browser. Leave it off on shared computers.
- Protect sensitive documents in transit. Protect PDF adds AES-256 encryption so only someone with the password can open the file. Send the password separately.
The bottom line: a visual signature records that you agreed; a certificate-based signature proves who signed and that nothing has changed. Both are “electronic signatures”. Knowing which one you’ve made lets you pick the right one for each document.