How to Sign a PDF on a Mac (Free, With Preview)
There's no need to print a document, sign it, scan it and email it back. Your Mac's free Preview app can add your real signature to any PDF in under a minute.
Step 1: Open the PDF in Preview
Double-click the PDF. It opens in Preview unless you've changed your default PDF app. If it opens somewhere else, right-click it and choose Open With > Preview.
Step 2: Show the Markup toolbar
Click the Markup button (a pen tip in a circle) at the top of the window. You can also press Shift + Command + A.
A second toolbar appears with drawing, text and signature tools.
Step 3: Create your signature (one time only)
Click the Sign button (it looks like a signature squiggle), then Create Signature. You have three options.
Trackpad
1. Click Click Here to Begin.
2. Sign on the trackpad with your finger.
3. Press any key when you're finished, then click Done.
2. Sign on the trackpad with your finger.
3. Press any key when you're finished, then click Done.
Camera
1. Sign your name in dark ink on a white piece of paper.
2. Hold it up to the camera so your signature sits on the blue line.
3. Preview captures it automatically. Click Done.
2. Hold it up to the camera so your signature sits on the blue line.
3. Preview captures it automatically. Click Done.
iPhone or iPad
1. Choose iPhone (or iPad) and select your device.
2. Sign on the device's screen with your finger or Apple Pencil.
3. Tap Done. It appears on your Mac.
2. Sign on the device's screen with your finger or Apple Pencil.
3. Tap Done. It appears on your Mac.
Your signature is saved, so next time you can skip this step. If you use iCloud, it's available on your other Macs too.
Step 4: Add the signature to the document
1. Click the Sign button again and choose your signature.
2. It appears on the page. Drag it into position.
3. Drag the corner handles to resize it.
2. It appears on the page. Drag it into position.
3. Drag the corner handles to resize it.
Step 5: Fill in the rest of the form
Many PDFs have fillable fields. Just click a field and type.
For PDFs without fields:
• Click the Text tool (T in a box) to add a text box, then drag it into place.
• Use Format > Show Fonts to change the size if needed.
• Use Format > Show Fonts to change the size if needed.
Step 6: Save and send
Press Command + S to save. To send a copy while keeping the original unchanged, use File > Export as PDF….
To share it straight away, click the Share button and choose Mail, Messages or AirDrop.
Is a Preview signature legally valid?
For many everyday documents, such as consent forms, delivery notes and simple agreements, an electronic signature like this is widely accepted. Some documents need a certified digital signature or a wet ink signature, so check with whoever sent the document if you're unsure.
Wrapping up
Set up your signature once. After that, signing any PDF is just Markup, Sign, drag, save.
