How to Sign a PDF on Mac

Sign a PDF on Mac with Preview

Preview opens PDFs by default on every Mac. Apple’s Preview User Guide gives these steps:

1. Open the PDF in Preview. If it opens in another app, Control-click the file, choose Open With and pick Preview.
2. Click the Show Markup Toolbar button if the toolbar is hidden, then click the Sign button.
3. Create a signature one of three ways:
   • Trackpad: click Trackpad, click the prompt text, sign with your finger on the trackpad, press any key, then click Done. On a Force Touch trackpad, pressing harder draws a darker line.
   • Camera: sign on white paper, hold it up to the camera level with the blue line, and click Done once it appears.
   • iPhone or iPad: click Select Device, sign on the device’s screen with your finger or Apple Pencil, and tap Done. This uses Continuity, so the devices must meet Apple’s Continuity requirements.
4. Click the signature to add it, drag it into place and use its handles to resize it.

With iCloud Drive turned on, the signature is also available on your other Macs. Preview fills in form fields you click on, and its AutoFill can insert your contact details. If the PDF came by email, double-click the attachment in Mail, sign it in Preview and choose File → Save, then Reply: Apple’s guide notes the signed PDF is attached to a new reply.

Sign a PDF on Mac in your browser with SigPDF

The editor above works in Safari, Chrome, Firefox and Edge on macOS. It is the better choice when you want a typed signature, separate initials and a date, or the same steps you use on an iPhone or a Windows PC.

1. Drag the PDF from Finder onto the box that says Drop your PDF here, or click the box to browse.
2. Create your signature. Drawing with a trackpad means pressing and holding while you move, which is awkward for most people. The Type tab is usually the cleaner option: enter your name and choose Elegant, Formal, Casual or Flowing. A photographed paper signature can be added later with Add Photo.
3. Click where the signature goes. Hover over it to reveal the resize square (lower right) and the delete button; drag the frame to move it.
4. Add the details. Add Initials, Add Date and Add Text put those items on the current page. Double-click a placed text, date or initials box to correct it. ⌘Z undoes the last change and ⌘⇧Z redoes it.
5. Download. Click Confirm & Download Signed PDF. The file, named after the original with “-signed”, lands in your Downloads folder. Without a plan you pick one first; the download follows the payment.

Preview or SigPDF? A quick comparison

When signing on a Mac goes wrong

• The PDF is password-protected. SigPDF cannot write into encrypted files. Open the PDF with its password, choose File → Print, pick Save as PDF from the PDF menu, and sign the saved copy.
• “This PDF can’t be edited.” The file is damaged or unusual. The same Print → Save as PDF route usually produces a clean copy.
• Preview’s Sign button is missing. Show the Markup toolbar first (the button with a pen tip).
• The camera does not pick up your signature.Use a thick dark pen on plain white paper in good light and keep the line of the signature level with the blue guide.
• Clicks on the page do nothing in SigPDF.Confirm the signature with Use This Signature first; only then does a click place it.

On an iPad, Apple Pencil makes drawing much easier; see how to sign a PDF on iPad. If you also work on a PC, the Windows guide covers Edge and Acrobat Reader.