How to Sign a PDF for Free — Every Method Explained

Published March 27, 2026

Whether it's a rental agreement, job offer letter, or client contract, you can sign a PDF for free without printing a single page. Here are the best methods for every device and situation.

Method 1: Adobe Acrobat Reader (Free)

Adobe Acrobat Reader — the free version — includes a signature tool that works without a subscription.

  1. Open your PDF in Adobe Acrobat Reader
  2. Click Fill & Sign in the toolbar (or find it under Tools)
  3. Click Sign yourself, then Add signature
  4. Type your name, draw it with your mouse, or upload an image of your signature
  5. Click Apply and place it on the document
  6. Save the signed PDF

This creates an electronic signature — not a legally-certified digital signature — but it's accepted for most personal and business documents.

Method 2: Mac Preview (Built-In, Completely Free)

Mac users don't need any extra software. Preview has a signature feature built in:

  1. Open the PDF in Preview
  2. Click the Markup toolbar button (pencil icon)
  3. Click the Signature icon (looks like a cursive S)
  4. Create a signature by drawing on your trackpad, signing on paper and scanning with the camera, or typing it
  5. Drag the signature to the right spot on the document
  6. Save the file

Preview saves your signature for future use, making this the fastest option if you're on a Mac.

Method 3: Sign on iPhone or iPad (Free)

iOS makes PDF signing simple through the built-in Markup tool:

  1. Open the PDF in the Files app or an email attachment
  2. Tap the Markup icon (pen icon in the top-right)
  3. Tap the + button at the bottom and choose Signature
  4. Draw your signature with your finger or Apple Pencil
  5. Drag and resize it to the correct field
  6. Tap Done and share or save

Method 4: Sign on Android (Free)

On Android, use Adobe Acrobat Reader (free app):

  1. Open the PDF in the app
  2. Tap the pencil edit icon
  3. Tap Fill & Sign
  4. Create or add your signature
  5. Place it on the document and save

Samsung devices also have a built-in PDF editor in Samsung Notes and the default file viewer.

Method 5: Free Online Signing Tools

If you need a quick one-off signature from any browser:

  • Smallpdf eSign: Upload PDF, add signature, download — free with limits
  • ILovePDF Sign: Simple drag-and-drop signature placement
  • DocuSeal: Free for personal use, privacy-focused
  • Signaturely: Free plan for up to 3 documents/month

Electronic Signature vs. Digital Signature

It's worth knowing the difference:

  • Electronic signature: An image or drawing of your signature added to the PDF. Free, widely accepted, but not cryptographically verified.
  • Digital signature: A cryptographic certificate that proves authenticity and detects tampering. Required for certain legal and government documents. Typically costs money.

For most everyday use — leases, offer letters, client agreements — an electronic signature is perfectly fine and legally binding in most countries.

How to Make Your Signature Look Good

Drawing with a mouse often looks messy. Better options:

  • Sign on paper, take a photo, and upload it to Adobe Reader or Smallpdf
  • Use a stylus or Apple Pencil on a tablet for a natural look
  • Use a touchpad on a laptop (more control than a mouse)

Quick Summary

Fastest free method on Mac: Preview — already installed, no signup.
Fastest free method on Windows: Adobe Acrobat Reader — free download.
Fastest free method on iPhone/iPad: Markup in Files app — no download needed.
Fastest free online method: Smallpdf or ILovePDF — upload and sign in one step.