Electronic signature vs digital signature
One is a picture of your name. The other is maths. Almost everything sold as the second is the first.
Free toolSign PDFDraw, type or upload a signature and put it on the page. The file you save is the file you dropped in with the ink appended, so the text in it is still text.Open the PDF signerThe short answer
An electronic signature is any mark you apply to a document to show you agree to it. A drawn name, a typed name, a tick in a box, a reply saying "I accept". A digital signature is one specific thing: a cryptographic hash of the document, encrypted with a private key that belongs to you, stored inside the file so a reader can check the document has not changed since you signed.
Every digital signature is an electronic signature. Almost no electronic signature is a digital one. The two words get used as if they meant the same thing, including by companies selling the first while saying the second.
| Electronic signature | Digital signature | |
|---|---|---|
| What it is | A picture, or any mark showing intent | An encrypted hash of the file's bytes |
| What it proves | That somebody put a mark there | That the file has not changed since signing |
| Needs a certificate | No | Yes, from an authority that vouches for you |
| Survives editing | Yes, and says nothing about the edit | No, it breaks and the reader says so |
| Costs money | No | Usually, and it involves proving your identity |
| In the file as | An image drawn on a page | A signature dictionary with a /ByteRange |
The one command that tells them apart
You do not have to trust anybody's marketing about this. A cryptographic signature has to record which byte ranges of the file it covers, in an entry called /ByteRange, and the PDF specification forbids that dictionary from living in a compressed object stream. The phrase is therefore always sitting in the plain bytes of a genuinely signed file, and always absent from one that only has a picture.
On macOS or Linux, in a terminal:
strings contract.pdf | grep ByteRangeOutput means there is a real digital signature. Silence means there is not, no matter how handwritten the mark on the page looks, and no matter what the tool that made it called itself.
What the free online signers actually produce
I signed the same 1,966 byte agreement through several of the tools ranking for "sign PDF" on 4 September 2026, then ran the test above on every file that came back.
| Signer | Size returned | Has a /ByteRange | Signature kind |
|---|---|---|---|
| iLovePDF | 45,410 B | no | electronic |
| floi | 6,237 B | no | electronic |
| Smallpdf | the returned file had no signature in it, so nothing is claimed | ||
| Signeasy | asks for an email address before it will sign, and none was given | ||
| Adobe Acrobat online | sign-in wall | ||
Neither file that could be tested carried a cryptographic signature. That is not a scandal and it is not a criticism of iLovePDF, which cannot issue you a private key any more than this site can. It is the answer to the question people are actually asking when they search for the difference: the free thing you are about to use makes a picture.
The PDF signer here makes a picture too, and says so on screen while you use it. The difference it does claim is about the rest of the file, not about cryptography: your original bytes are appended to rather than replaced, so the document you send back is still the document you were sent.
How rare digital signatures actually are
The distinction sounds urgent until you look at what arrives in real life. I ran the /ByteRange test across every PDF sitting in one working machine's downloads folder on 4 September 2026: bank statements, invoices, earnings reports, a company onboarding guide, contracts, and things saved off the web.
| PDFs scanned | 37 |
|---|---|
| Carrying a cryptographic signature | 0 |
Not one. That includes documents from banks and payment processors, which are exactly the senders you would expect to sign. Whatever the compliance literature implies, the ordinary PDF economy runs almost entirely on electronic signatures and on trusting the channel the file arrived through.
This is one machine and one folder, so treat it as a sample rather than a survey. Run the same command on your own folder. The result is usually the same, and it takes a second.
Which one you need
Most of the time the picture is the right answer, because the counterparty is not going to verify a certificate and the risk is low. The cases where it is not are specific.
| Your situation | What to use |
|---|---|
| A client contract, an NDA, a supplier form | Electronic. Sign it, send it, keep the email thread as the trail. |
| A form a school, landlord or employer sent you | Electronic. They are checking that you filled it in, not verifying a key. |
| Anything where somebody named a standard | Read which one. "Qualified" or "advanced" means a certificate is required. |
| Tenders, regulated filings, some government portals | Digital, usually a qualified certificate from a named authority. |
| You are the one who will need to prove it later | Digital, or an audit trail from a service that keeps one. |
The middle row is the one that catches people out. If a request mentions eIDAS, a qualified electronic signature, or an advanced electronic signature, a drawn name will be rejected and no free browser tool will help. Those words are the signal to stop and get a certificate.
Are electronic signatures legally binding?
In most places, for most everyday agreements, yes. The relevant law says a signature is not invalid merely because it is electronic. It does not say every electronic signature is strong.
| Where | The law | The gist |
|---|---|---|
| United States | ESIGN Act, UETA | Electronic signatures and records are valid. Consent and intent matter. |
| European Union | eIDAS | Three tiers. Only the qualified tier is automatically equal to handwriting. |
| United Kingdom | Electronic Communications Act, UK eIDAS | Admissible in evidence. The court weighs how reliable it was. |
What changes between a picture and a certificate is not usually validity, it is what you can show if the other side denies signing. A picture on its own shows very little. The email it travelled in, the timestamps, and the record of who had access are what carry the weight, which is why the paid services sell an audit trail rather than better ink.
Common exclusions include wills, some property transfers, some family law documents and some court filings, and they differ by country. None of this is legal advice. For anything that would genuinely hurt to lose, ask somebody qualified in your jurisdiction.
How to get a real digital signature
No page in a browser can give you one, including this site, for the reason in the FAQ below: the private key has to be yours. Three routes are real, and they are listed cheapest first.
A self signed certificate
Free, and available in Adobe Acrobat Reader through Use a Certificate, or with
opensslif you prefer. The maths is genuine and the file gets a real/ByteRange. What it lacks is anybody vouching for you, so readers show it as signed but not trusted. Useful for detecting tampering between two parties who already know each other. Not useful for convincing a stranger.A certificate from a public authority
You prove your identity to a certificate authority, they issue a certificate, and PDF readers trust it because they trust the authority. This is what "advanced" means in eIDAS terms. Expect an annual fee and an identity check.
A qualified certificate on hardware
The top eIDAS tier. The key lives on a smart card, a USB token or a certified remote service, and is legally equivalent to a handwritten signature across the EU. This is what tenders and regulated filings mean when they ask for a qualified signature.
If none of that applies to what you are doing, and for most people it does not, an electronic signature is the correct tool and there is no reason to pay for anything.
Signing a PDF without any of this
For the ordinary case, putting your name on a page, the thing worth caring about is not the cryptography. It is whether the file survives.
Most online signers rebuild your PDF. They open it, render it through their own engine, and hand back a new file with your signature in it. The text usually survives, the fonts usually survive, and the bytes do not: the same 1,966 byte agreement came back from iLovePDF at 45,410 bytes, 23 times the size, with none of the original in it. For a contract that is a real difference, because what you return is no longer the document you were sent.
The PDF signer on this site appends instead, which is a thing the PDF format has always allowed. Your file is copied out byte for byte and a short section is added after it. Measured across ten real PDFs from 1,966 bytes to 2.1 MB, every one came back with the original bytes intact and gained between 4,256 and 4,668 bytes. It is still an electronic signature. It is just an electronic signature that leaves your document alone.