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

What an electronic signature is, what a certificate-based digital signature adds, which one the law requires for which documents, and how to sign a PDF properly.

NewKitApp19 de octubre de 2026 9 min de lectura

Nuestras guías están disponibles en inglés e indonesio. Los artículos de abajo se abren en inglés.

Someone emails you a rental agreement and asks you to "sign and send it back". Another email asks for a "digital signature" on a tender form. A government portal demands a "qualified electronic signature". These phrases sound interchangeable and they aren't. Mixing them up can mean a document that gets rejected, or worse, a signature that's hard to defend if a dispute comes up.

This guide explains the two main kinds of signatures you'll meet on PDFs, what each one proves, what the law in several major jurisdictions says, and how to sign properly in each case.

The short version

An electronic signature is any electronic sign of agreement: a typed name, a drawn signature, a picture of your handwritten signature placed on a document, even a click on "I agree". It shows intent to sign.
A digital signature is a specific technology. It uses cryptography and a digital certificate to bind a signer's identity to a document and to detect any change made after signing.

All digital signatures are electronic signatures. Most electronic signatures are not digital signatures.

Electronic signatures in detail

When you draw your signature on a tablet, type your name in a cursive font, or place a scanned image of your signature on a PDF, you create an electronic signature. The Sign PDF tool on NewKitApp does exactly this: it puts an image of your signature on the page where you choose.

What an electronic signature proves depends mostly on context, not on the image itself:

Intent. By placing your signature, you showed you meant to agree.
Attribution. The surrounding evidence links the signature to you: you sent it from your email account, the other party received it from you, you referred to it in later messages.
Integrity, weakly. Unless something else protects the file, anyone could edit the document after you signed.

For most everyday agreements, that's enough. Courts in most countries accept electronic signatures for ordinary contracts, and in disputes they look at the overall evidence: emails, timestamps, conduct of the parties.

Digital signatures in detail

A digital signature works with a pair of cryptographic keys. The signer holds a private key, often on a smart card, a USB token, or in a secure cloud service. A matching public key sits inside a digital certificate issued by a certification authority (CA) that has checked the signer's identity.

When you sign:

Software calculates a "hash" of the document, a short fingerprint unique to its exact contents.
Your private key encrypts that hash. The result is the signature, embedded in the PDF with your certificate.

When someone opens the document:

Their reader calculates the hash of the document as it is now.
It uses your public key from the certificate to decrypt the signature and recover the original hash.
If the two hashes match, the document hasn't changed since you signed. If they differ, the reader shows the signature as invalid.
The reader checks that your certificate was issued by a trusted CA and wasn't revoked.

That gives three guarantees an image can't: identity (a CA vouched for who you are), integrity (any change breaks the signature) and non-repudiation (only your private key could have produced it).

In Adobe Acrobat and other readers, a digitally signed PDF shows a signature panel with a green check mark or a warning, and details about the signer and the certificate.

What the law says

Laws vary, but many countries follow a similar tiered pattern. This is a general overview, not legal advice.

European Union: eIDAS

The eIDAS Regulation defines three levels:

Simple electronic signature (SES): any electronic data used to sign. A drawn or typed signature counts. Courts can't reject it just because it's electronic.
Advanced electronic signature (AES): uniquely linked to and capable of identifying the signer, under the signer's sole control, and able to detect later changes. In practice, a certificate-based digital signature.
Qualified electronic signature (QES): an advanced signature created with a qualified signature device and a qualified certificate from a trusted provider on the EU Trusted List. A QES has the same legal effect as a handwritten signature across all member states.

Most commercial contracts can use SES. Some acts, often in public administration, notarial work and certain employment documents, require AES or QES.

United States: ESIGN and UETA

The federal ESIGN Act and the state-level Uniform Electronic Transactions Act give electronic signatures the same validity as handwritten ones for most transactions, provided the parties agreed to do business electronically. They don't require any particular technology. Exceptions include wills, some family law documents, court orders and certain notices such as utility shutoffs.

Indonesia: ITE Law and its regulations

Indonesia's Electronic Information and Transactions Law and Government Regulation 71 of 2019 distinguish between certified electronic signatures, created with a certificate from a certification provider registered with the government, and uncertified ones. Both are legally valid, but certified signatures carry stronger evidentiary weight. Many government services and some financial processes require certified signatures from a registered provider.

Brazil, India and elsewhere

Brazil's Law 14.063 of 2020 sets simple, advanced and qualified levels, with ICP-Brasil certificates for the qualified level. India's IT Act recognises electronic signatures and treats Aadhaar-based eSign and digital signature certificates as the main trusted forms. Many other countries follow similar models.

Documents that usually can't be signed electronically

Across jurisdictions, some documents still often need wet ink or a notary: wills and testaments, property transfers and deeds, some powers of attorney, marriage-related documents, and court filings in certain courts. Always check the rules for the specific document.

Which one do you need?

Ask three questions.

1. Did the recipient specify? If a government portal, a bank or a tender asks for a "digital signature", "certified signature" or "qualified signature", an image of your signature won't do. Use the service they name or a certificate from an approved provider.

2. How much is at stake? For a gym membership, a freelance agreement under a few thousand dollars, a school permission slip or an NDA, an electronic signature is normal practice. For a large commercial contract, consider a dedicated e-signature platform that records an audit trail, or a digital signature.

3. How likely is a dispute? If you expect the other party might later deny signing, stronger evidence helps. An audit trail (who opened the document, from which email address and IP, when) or a digital signature gives you that.

How to sign a PDF with an electronic signature

For the everyday case, here's a clean process using browser tools that keep the document on your device.

Open the document in Sign PDF.
Create your signature. Draw it with a mouse, finger or stylus; type your name in a handwriting font; or upload a photo of your signature on white paper (the tool removes the white background).
Place it. Drag it to the signature line and resize it with the corner handle. Use the page arrows to add initials on other pages.
Add the date if the form asks for it. The Watermark tool can add small text, or fill the date field in your PDF reader before signing.
Download the signed PDF.
Optionally flatten it. Flatten PDF with the whole-page option merges the signature into the page image, so nobody can lift it off the page as a separate object.
Send it from your usual email address. That email becomes part of the evidence that you signed.
Keep a copy of both the unsigned and signed versions.

Tips for a better-looking signature

Sign larger than you need, then scale down. Small signatures drawn with a mouse look shaky.
Use a stylus or your finger on a phone if you can.
Blue ink helps people tell your signed original from a black-and-white copy.
If you upload a photo, shoot it in daylight on plain white paper, holding the phone parallel to the page.

Protecting a signed PDF

An image signature doesn't stop anyone from editing the document afterwards. A few steps raise the bar:

Flatten so form fields and the signature become part of the page.
Encrypt with Protect PDF and disallow editing, so ordinary readers won't modify it.
Keep the version you sent and the email you sent it with.
Compare any returned copy with your version using Compare PDF. If someone changed a figure or a clause, it shows up highlighted.

None of these give the cryptographic guarantee of a digital signature, but together they make tampering obvious and leave a clear record.

How to create a digital signature

If you need a certificate-based signature:

Get a certificate from a certification authority. In the EU, choose a qualified trust service provider if you need QES. In Indonesia, use a provider registered with the Ministry of Communication and Digital Affairs. Many countries also issue national ID cards with signing certificates.
Install the provider's software or use their cloud signing service.
Sign in a compatible application. Adobe Acrobat (including the free Reader for some workflows), the provider's own app, or a platform such as DocuSign or a government signing portal.
Don't edit the file after signing. Any change, even rotating a page or compressing the file, invalidates the signature. Compress, merge and number pages before signing.

That last point catches people out. Run every other PDF tool first, then apply the digital signature as the very last step.

Common misunderstandings

"A scanned signature isn't legal." It usually is, for ordinary agreements. What matters is intent and evidence.

"A digital signature is just a fancier electronic signature." It's a different mechanism with stronger guarantees, especially about integrity.

"Typing my name in an email is a signature." In many jurisdictions, it can be, if the context shows intent to be bound. Be careful what you agree to in email.

"If I sign with an image, the document can't be changed." It can. Only a digital signature detects changes.

"I can use any certificate." For qualified or certified signatures, the certificate must come from a provider recognised in the relevant jurisdiction.

The middle ground: e-signature platforms

Between a plain image signature and a certificate-based digital signature sits a third option many businesses use: dedicated e-signature platforms such as DocuSign, Adobe Acrobat Sign, Dropbox Sign or local providers. They work like this:

You upload the document and enter the signers' email addresses.
Each signer receives a link, opens the document in the browser, and signs by drawing or typing.
The platform records an audit trail: when each email was sent and opened, the IP address and device used, the moment of signing, and a hash of the final document.
When everyone has signed, the platform seals the PDF with its own digital signature and attaches a certificate of completion.

The individual signatures are still simple electronic signatures, but the platform's seal protects integrity, and the audit trail strengthens attribution. For contracts with clients, employment offers and leases, this is often the sensible level.

The trade-off is that the document goes to the platform's servers. Choose one with clear data handling terms, and check whether your sector or country requires data to stay in a particular region.

Signing on a phone

Many people sign on the move. The browser approach works well on phones:

Open the PDF from your email or Files app, then open Sign PDF in the browser and choose the file.
Draw with your finger in the signature box. Rotate the phone to landscape for more room.
Place the signature with one finger and resize it with the corner handle.
Download, then attach the signed file to your reply.

Your signature never leaves the phone, and you don't need to install an app that asks for access to all your files.

Summary

Use an electronic signature, such as a drawn or typed signature placed on the PDF, for everyday agreements where the other party accepts it. Protect the signed file by flattening and encrypting it, keep records, and compare returned copies. Use a certificate-based digital signature when a law, a regulator or the recipient requires it, or when the stakes justify stronger proof, and apply it as the last step after every other edit.

Knowing which one you need saves you from rejected filings and gives you the right level of evidence when it counts.