The short answer
Open the PDF in a signing tool, draw or type your signature, drag it onto the signature line and save a new copy. You can do this free in your browser with our Sign PDF tool, in Adobe Acrobat Reader (Fill & Sign), in Preview on a Mac, or with Markup on an iPhone. No printer or scanner needed.
Printing a form, signing it with a pen, scanning it back in and emailing a slightly crooked, gray copy is still how a lot of people sign documents. It takes ten minutes and needs a printer you may not have. For most everyday paperwork — rental agreements, school forms, invoices, offer letters — signing on screen is quicker, looks cleaner and is accepted.
Here's how to do it on any device, plus the part most guides skip: when a signature like this is enough, and when it isn't.
On this page
Sign a PDF in your browser (any computer or phone)
- 1Open Sign PDF and drop in your document.
- 2Choose Draw it and sign with your mouse, trackpad, finger or stylus — or choose Type it and enter your name.
- 3Pick the page (the last page is selected for you, since that's where most signature lines are).
- 4Tap the page where the signature goes, drag it into place and adjust the size.
- 5Download the signed PDF.
Everything happens on your device; the contract isn't uploaded to a server. That matters more than it sounds — the documents people sign usually contain addresses, salaries, bank details or ID numbers.
Make a drawn signature look natural
Sign bigger and slower than feels natural; it's scaled down when you place it, which smooths out wobbly lines. On a phone, turn it sideways for a wider signing area.Other free ways to sign
| Device | Built-in or free option | Where to find it |
|---|---|---|
| Windows, Mac, Linux | Any modern browser | Sign PDF |
| Windows or Mac | Adobe Acrobat Reader (free) | Fill & Sign → Sign |
| Mac | Preview | Markup toolbar → Signature |
| iPhone / iPad | Markup | Open the PDF in Files or Mail → Markup → + → Signature |
| Android | Browser, or a PDF app | Sign PDF works in Chrome on Android |
The built-in options are handy if you already use those apps. A browser tool is useful when you're on someone else's computer, on Android, or don't want to install anything.
Is a signature like this legally valid?
For most everyday documents, yes. Laws such as the US ESIGN Act and UETA, the EU's eIDAS regulation and the UK's electronic signature rules treat an electronic signature as valid when the signer clearly intended to sign. A drawn or typed signature placed on a PDF is a simple electronic signature.
There are limits, though, and they're worth knowing before you sign something important:
- Some documents need more. Wills, some property and court documents, and certain government filings may require a wet-ink signature, a witness, or a specific certified signature, depending on the country.
- The other party decides what they accept. A bank or government office may insist on its own signing system.
- A simple signature doesn't prove who signed or that nothing changed. That's fine between people who trust each other; for high-value contracts, a certificate-based service adds an audit trail.
Electronic signature vs digital signature
The two terms sound interchangeable but describe different things:
| Simple electronic signature | Digital (certificate) signature | |
|---|---|---|
| What it is | An image of your signature, or your typed name | A cryptographic seal tied to a verified identity |
| Shows tampering? | No | Yes — any change after signing is flagged |
| Needs an account or certificate? | No | Yes |
| Good for | Forms, letters, invoices, agreements between people | Regulated contracts, official filings |
Our Sign PDF tool creates a simple electronic signature. If a document asks for a “digital signature” specifically, that usually means the certificate kind.
Before you send the signed PDF
- Check every place that needs you. Some forms want initials on every page as well as a full signature at the end.
- Fill in the date and other fields first. If the form has fillable boxes, complete them in your PDF reader (Acrobat Reader, Preview or your browser's PDF viewer), save, and add your signature last.
- Keep a copy. Save the signed version with a clear name like
lease-2026-signed.pdf. - Combine if asked. If you need to return several signed documents as one file, merge the PDFs after signing.
- Sending a picture instead? Some portals only accept images. Turn the signed page into a JPG with PDF to JPG.
Frequently asked questions
Can I sign a PDF on my phone?
Yes. On iPhone, use Markup in the Files or Mail app, or open a browser signing tool. On Android, a browser tool like Sign PDF works in Chrome — draw your signature with your finger.
Is it safe to sign PDFs online?
Only if you trust where the file goes. Many sites upload your document to their servers. A tool that works in your browser never sends the PDF anywhere, which is safer for contracts and forms with personal details.
Can someone copy my signature from the PDF?
Yes — like a scanned signature, the image can be copied. That's true of any signature sent as a file. For documents where this matters, use a certificate-based signing service.
Do I need Adobe to sign a PDF?
No. Adobe Acrobat Reader is one free option, but browser tools, Preview on Mac and Markup on iPhone all work without it.
Can I edit a PDF after signing it?
With a simple signature, the PDF can still be edited, which is why it doesn't prove nothing changed. Add your signature last, after all other changes are done.
OnlineToolPro Editorial Team
Builds and tests the tools on this site
The team behind OnlineToolPro. We write guides from building and testing these tools, and check platform rules against official documentation such as YouTube Help. When something changes, we update the article and its date.