Electronic vs Digital Signature, What the Difference Means for Your Contracts

An electronic signature is any electronic sign that a person agrees to a document, while a digital signature is a specific cryptographic method that ties a file to a certificate and exposes any later change. Most contracts need an electronic signature to be valid. A digital signature makes it far easier to prove.

The two terms get used as if they meant the same thing, and vendors do not always help. The distinction matters because it changes what you can prove if a contract is ever disputed. This article explains both, how they work together, and what to look for in the documents your team signs.

What counts as an electronic signature

The legal definition is broad on purpose. The US ESIGN Act describes an electronic signature as an electronic sound, symbol, or process attached to or logically associated with a record and executed or adopted by a person with the intent to sign it. The EU eIDAS Regulation uses similar language, data in electronic form attached to or logically associated with other data and used by the signatory to sign.

Under those definitions, all of these can be electronic signatures:

• A drawn or typed signature placed on a PDF in a signing tool
• Clicking an "I agree and sign" button after reading terms
• Typing your name at the end of an email that accepts an offer
• A recorded "yes" on a phone line, in some contexts

Notice what the definition does not require. No certificate, no special device, no cryptography. What it requires is intent. The person meant to sign. That is why the legal question around an electronic signature is almost always about evidence: can you show that this specific person intended to sign this specific document?

What a digital signature is

A digital signature is a technique, not a legal category. It uses public key cryptography to bind a document to a signing key. The process looks like this:

1. The software calculates a hash of the document, a short fingerprint derived from every byte of the file.
2. The hash is encrypted with a private key that only the signer, or the signing service, controls.
3. The result is embedded in the file together with a certificate that contains the matching public key.
4. Anyone opening the file can use the public key to check that the hash still matches the content. If even one character changed, it no longer matches.

For PDFs, the common standard for this is PAdES, a set of rules for embedding signatures in PDF files that standard PDF readers understand. When you open a properly sealed PDF, the reader's signature panel tells you whether the document has been modified since it was signed.

Who holds the certificate

There are two common setups. In the first, each signer has a personal certificate issued after an identity check, often stored on a card, a token or a remote signing service. In the second, the signing platform applies its own certificate to the completed document as a seal, after it has collected each signer's electronic signature and recorded the evidence. Business e-signature tools usually use the second approach, because asking every client to obtain a personal certificate would stop most contracts from ever getting signed.

How the two fit together

The cleanest way to think about it: the electronic signature is the act of agreeing, and the digital signature is the lock on the envelope afterwards.

A well built signing process uses both. Each signer applies an electronic signature in the browser, the platform records how they were identified and when they acted, and then the finished PDF is digitally sealed so that the content and the evidence cannot be changed without it showing.

Why the difference matters for your contracts

Disputes are about evidence

Contract disputes rarely hinge on whether electronic signatures are allowed. They hinge on whether the other side can deny signing, or claim the document was altered. A signature image pasted on a page answers neither question. A sealed file with an audit trail answers both. It shows the signer's email, the time in UTC, the IP address and browser used, and a fingerprint of the document before and after signing. Our audit trail page shows what that record looks like.

Tampering becomes visible

Without a digital seal, a PDF can be edited after signing and nothing in the file reveals it. With one, the reader flags the change immediately. That protects both parties. Your client knows you did not change the payment terms after they signed, and you know they did not either.

Some documents need more than a simple signature

In the EU, eIDAS defines three levels: simple, advanced and qualified. A qualified electronic signature requires a certificate from a qualified trust service provider and a qualified signature creation device, and it is the only level that automatically has the same effect as a handwritten signature across member states. Some national laws require it for certain documents. Most commercial agreements do not need it. Our eIDAS page explains each level and where each one is used.

The three eIDAS levels in plain terms

Simple electronic signature

Any electronic signature that meets the basic definition. Admissible in court in every member state. A court weighs the evidence like any other.

Advanced electronic signature

Article 26 of eIDAS sets four requirements. The signature is uniquely linked to the signer, capable of identifying the signer, created with data the signer can use under their sole control with a high level of confidence, and linked to the signed data so that any later change is detectable. In practice this means stronger identity checks, such as a one-time code sent to the signer's email and phone, plus a digital seal on the result.

Qualified electronic signature

An advanced signature created with a qualified device and based on a qualified certificate. It requires an identity check by a qualified provider. We do not offer qualified signatures, and we say so openly, because pretending otherwise would put a customer's document at risk.

What about the United States

US law does not use tiers. ESIGN and UETA give electronic signatures legal effect when the signer intends to sign, consents to doing business electronically where consent is required, the signature can be attributed to the person, and the record is kept accurately. A digital seal is not required, but it is one of the clearest ways to show the record was kept accurately and has not changed. The ESIGN Act and UETA page goes through each requirement.

Questions to ask about any signing tool

• Is the final PDF digitally sealed? Open a completed document in a standard reader and check the signature panel.
• What does the audit certificate record? Look for timestamps in UTC, IP address, browser, signer email and document hashes.
• How are signers identified? Email link only, or a one-time code by email or SMS before signing?
• Can a third party verify the file? A verification page that checks a file's fingerprint against the platform's records is useful when the other side's lawyer asks questions.
• Is the vendor honest about what it does not do? If a tool claims to offer qualified signatures, ask which qualified trust service provider issues the certificates.

A practical example

Say your agency sends a statement of work to a client. The client's operations lead signs first, then your director countersigns. In a sound process, each of them receives a link by email, reviews the document in the browser and applies a drawn or typed signature. The platform records each step. When the director signs, the platform stamps both signatures into the PDF, adds the audit certificate as the final page and applies its digital seal. Both parties receive the same sealed file.

Six months later, the client disputes a clause. You open the PDF, the reader confirms the file has not changed since signing, and the certificate shows the client's operations lead opened the email, viewed the document and signed at a specific time from a specific IP address. The question of whether the electronic signature counts never comes up, because the evidence answers it.

That combination is what our electronic signature software produces on every plan. The plans are listed on the pricing page. You can see the result on your own PDF with the demo, and read how to sign a PDF electronically for the full workflow.

The short version

An electronic signature is what makes the agreement. A digital signature is what makes it hard to argue with. For everyday business contracts, you want a simple or advanced electronic signature from each signer, backed by an audit trail and a digitally sealed final PDF. For the small set of documents that legally require a qualified signature, use a qualified trust service provider.

This article is general information for business teams, not legal advice. For a specific document, ask a lawyer admitted in the relevant jurisdiction.

Frequently asked questions

Is a digital signature the same as an electronic signature?

No. An electronic signature is any electronic sign of intent to agree. A digital signature is a cryptographic technique based on a certificate and a hash that shows who sealed a file and whether it changed afterwards. A digital signature is one way to implement or protect an electronic signature.

Which one do I need for a business contract?

An electronic signature from each signer is what forms the agreement. A digital seal on the final PDF, together with an audit trail, is what makes it easy to prove. Sound signing tools give you both.

Is a digital signature more legally valid?

In the United States the law is technology neutral, so neither is preferred. In the EU a qualified electronic signature, which relies on digital signature technology and a qualified certificate, has the same legal effect as a handwritten one. Other levels are still admissible as evidence.

How can I tell whether a PDF is digitally signed?

Open it in a standard PDF reader and look for the signature panel. It shows who applied the seal and whether the document has been modified since.