How to Sign a PDF: 6 Free Ways, Step by Step

Which method should you use?

Short version: for a form that is just for you, any of them is fine. For a contract, a lease or an estimate that goes to a client, use a method that keeps a record of the signature.

1. Online, in any browser (MultiDocs)

This works the same on an iPhone, an Android phone, a Chromebook or a work computer where you can't install anything.

1. Open Sign a PDF and tap “Choose document.” Pick the PDF, or a photo of the paper document. You can also scan a page with your phone camera.
2. Choose “Just me.”
3. Tap “Add my signature” and draw it with your finger, mouse or trackpad.
4. Drag it into place on the right page. Add the date, your name or a checkbox if the form asks for them.
5. Tap “Finish” and download the signed PDF, or send it by email.

It's free and unlimited when you're the only one signing, with no account and no watermark. The file is processed in your browser, so it never leaves your device. The signed PDF includes a signature record on the last page with the date, time and the document's SHA-256 fingerprint, which anyone can check at /verify.

2. Adobe Acrobat Reader (Fill & Sign)

Acrobat Reader is the free version of Adobe's PDF app. Its Fill & Sign tool lets you add a signature without paying.

1. Open the PDF in Acrobat Reader.
2. Open the Fill & Sign tool (in recent versions, from “All tools,” or the pen icon in the toolbar).
3. Choose “Sign” and then “Add signature.” Type your name, draw it, or upload a picture of your signature.
4. Click “Apply,” then click where the signature goes and resize it.
5. Save the file (File › Save As) so you keep the original untouched.

Menus move around between versions, but “Fill & Sign” has kept its name for years. Note that sending the document to someone else for their signature uses Acrobat Sign, which has only a couple of free requests a month (see free e-signature plans compared).

3. Preview on a Mac

Every Mac has Preview, and it signs PDFs well.

1. Open the PDF in Preview (double-click it, or right-click › Open With › Preview).
2. Click the Markup button (the pen tip) to show the Markup toolbar.
3. Click the Sign button and then “Create Signature.” Sign on the trackpad with your finger, hold a signature on white paper up to the camera, or draw it on your iPhone or iPad.
4. Choose your signature, then drag and resize it on the page.
5. Save it with File › Save, or File › Export as PDF to keep a copy.

Preview remembers your signature, so next time it's two clicks.

4. iPhone or iPad (Markup)

1. Open the PDF in the Files app, or tap the attachment in Mail.
2. Tap the Markup button (the pen tip).
3. Tap the “+” button and choose “Add Signature.” Draw it with your finger the first time; your iPhone saves it.
4. Drag it into place and resize it with the corners.
5. Tap “Done” and share or save the PDF.

Full walkthrough, including Safari and Mail: how to sign a PDF on iPhone.

5. Android

Android has no single built-in signing tool, and menus vary by phone maker. Three options that work:

• In the browser: open Sign a PDF in Chrome and follow the same steps as above. Nothing to install.
• Adobe Acrobat Reader app: open the PDF, tap “Fill & Sign” in the bottom menu, tap Signature › Add signature, draw it and tap where it goes.
• Google Drive: recent versions of the Drive app let you open a PDF and annotate it with a pen, which you can use to sign by hand. It doesn't save a reusable signature.

Step by step: how to sign a PDF on Android.

6. Microsoft Edge on Windows

Edge is the default PDF reader on most Windows computers.

1. Open the PDF in Edge (right-click › Open with › Microsoft Edge).
2. Choose “Draw” in the PDF toolbar and pick a pen color and thickness.
3. Sign with the mouse, a touchscreen or a stylus.
4. Save with the save icon or Ctrl+S (or “Save as” to keep the original).

It's simple, but signing with a mouse rarely looks great and Edge doesn't store a signature to reuse. Some newer Edge builds show extra Adobe-powered PDF tools; a few of those ask you to sign in to Adobe.

When someone else has to sign

The five built-in tools above all have the same limit: they draw a signature on the page. They don't record who signed, when, or from where, and anyone with the signed file can copy the signature image. That's fine for your own forms. It's weak for a contract, a lease or an estimate where the other side might later say “I never signed that.”

To get a signature from another person, send the document for signature: mark where they sign, send a link by email, text message or WhatsApp, and they sign on their phone without creating an account. The signed PDF comes back with an audit trail: the email or phone the link went to, the IP address, device, date and time, and the document's fingerprint. MultiDocs includes 15 requests a month for free.

Is a signature on a PDF legally binding?

Yes, for almost every private document. The federal ESIGN Act defines an electronic signature as an electronic “sound, symbol, or process” attached to a record and adopted with the intent to sign it (15 U.S.C. § 7006(5)). A drawn signature on a PDF fits that definition, and so does a typed name. State law (UETA, adopted almost everywhere) says the same.

The question in a dispute is usually not “is it a signature?” but “can you prove who made it?” That's where an audit trail helps. A few documents, such as wills and some court and family law papers, are excluded: see documents that can't be e-signed and are electronic signatures legally binding?

Tips for a clean signature

• Sign slowly and big; every tool shrinks it to fit.
• Go to the right page before you place the signature. Long contracts often ask for initials on each page too.
• Keep the original PDF and save the signed copy under a new name.
• Don't “print to PDF” after signing: it flattens the file and changes its fingerprint, so a verification check will fail.