Sign a PDF on your Mac with Preview, no printer needed

Why it happens

Preview, the app that opens PDFs on every Mac, has a signing tool built into its Markup toolbar. You make your signature once, by drawing on the trackpad or showing a signed piece of paper to the camera, and Preview keeps it for next time. No printing, scanning or extra apps.

How to fix it

1. Double-click the PDF to open it. If it opens in another app, Control-click the file, choose Open With and pick Preview. Want an unsigned copy too? Select the file in Finder and press Command-D first.

2. Click the Markup button in the toolbar (a pen tip in a circle) so the Markup tools appear, then click Sign.

   Preview›Markup›Sign

3. Click Create Signature. Choose Trackpad to sign with your finger, or Camera to sign on white paper and hold it up to the camera. If you have an iPhone or iPad nearby, you can sign on that instead.

4. When it looks right, click Done. Then click Sign again and choose your signature to put it on the page.

5. Drag the signature onto the line and drag a corner to resize it. Press Command-S to save the signed PDF.

Still not fixed?

1. If the form has boxes for your name and date, click a box and type. If it has no boxes, open the Markup tools and use the Text tool to add text anywhere.

   Preview›Markup›Text

2. If the Markup tools are greyed out, the PDF may be locked by whoever made it. Ask them for a copy that allows changes, because Preview can't sign a protected file.

3. If your trackpad signature comes out shaky, try Camera instead. A thick black pen on plain white paper gives the cleanest result.

4. If Preview won't open the PDF at all, the file may be damaged. Ask for it again, and if Preview fails with every PDF, contact Apple Support.