How to sign a PDF
To sign a PDF yourself, use the free tool already on your device: Preview on a Mac, Acrobat Reader on Windows or Android, Markup on an iPhone. When someone else has to sign, or you need proof of who signed and when, send it through an e-signature service instead.
By docuinked. Published 2026-11-08, updated 2026-11-08.
The short answer, by device
| You're on | Free tool | Where the signature button is | Full steps |
|---|---|---|---|
| Mac | Preview (built in) | Markup toolbar, then Sign | Sign a PDF on a Mac |
| Windows | Adobe Acrobat Reader (free download) | Sign or Fill & Sign, then Add signature | Sign a PDF on Windows |
| iPhone or iPad | Files app with Markup (built in) | Markup, then the plus button, then Add Signature | Sign a PDF on an iPhone |
| Android | Adobe Acrobat Reader (free app) | Fill & Sign, then the signature pen | Sign a PDF on Android |
| Chromebook | Gallery app (built in) | Toolbar signature button, then Place signature | Sign a PDF on a Chromebook |
Every one of these puts a picture of your signature on the page. That is enough for most forms you fill in and send back yourself.
Two different jobs
You sign and send it back. A lease addendum, a school form, a permission slip. Use the built-in tool above, save, and email the file. Nothing else is needed.
Someone else signs, or several people do. A contract with a client, an offer letter, an NDA. Emailing a PDF back and forth works, but you end up with copies that don't match and no record of who opened what. An e-signature service sends each person a link, collects every signature on one copy, and keeps a log of each step.
What "signing" a PDF actually proves
A signature image proves very little on its own. Anyone can copy it onto another file, and anyone can edit the PDF after you sign. If the document ever matters in a dispute, what helps is the record around the signature: who got the link, when they opened it, when they signed, and a way to show the file hasn't changed since. We explain the difference in electronic vs digital signatures.
Where docuinked fits
docuinked is for the second job. You upload the PDF, place the fields, and add the people who sign, including yourself if you sign too. Each signer gets a link, signs on any phone or computer, and never needs an account. The finished file is sealed so any change after signing shows, and it comes with a certificate of completion.
Your first 5 completed documents are free, with no card, and signers never pay. You do need an account to send. See the pricing or create a free account.
Common questions
How do I sign a PDF without printing it?
Open it in the free tool on your device, add your signature with the signature button, and save. Preview, Markup and Acrobat Reader all let you draw your signature once and reuse it.
Can I just type my name instead of drawing it?
Often yes. Acrobat Reader has a Type option, and a typed name can count as an electronic signature if you meant it as one. If the form asks for a handwritten-style signature, draw it.
Is it safe to sign a PDF on a free website?
Read what the site does with your file before you upload it. A contract can hold addresses, salaries or account numbers. The built-in tools on your Mac, PC or phone never send the file anywhere.
How do I get someone else to sign a PDF?
Send it through an e-signature service so each person gets their own link and everyone ends up with the same signed copy. With docuinked you upload the PDF, place their fields and send. They sign without an account.
Related
Try it in test mode
Free during the beta. Test keys send no email, so you can build the whole flow first.