How to sign a PDF in Preview on a Mac
Preview is the Mac's built-in PDF app, and its Sign tool covers most everyday signing. This guide goes deeper than the basics: which of the three ways to capture a signature looks best, how to type on a form with no fields, how to add a date, and what to do when the signature lands in the wrong place.
Updated November 5, 2026 · 3 min read
On this page
The quick version
- 1
Open the PDF in Preview
Double-click it. If another app opens instead, Control-click the file and choose Open With, then Preview.
- 2
Click Sign
Click Show Markup Toolbar if the toolbar is hidden, then the Sign button. Saved signatures are listed there.
- 3
Place and save
Click a signature to drop it on the page, drag it onto the line, resize it with the handles, and press Command-S.
Pick the best way to capture your signature
The first time you click Sign, Preview asks how to create one. All three are free; they just look different on the page.
| Option | How it works | Best for |
|---|---|---|
| Trackpad | Sign on the trackpad with a finger, press any key, then click Done. On a Force Touch trackpad, pressing harder makes the line darker. | Quick signatures when you have nothing else to hand |
| Camera | Sign on white paper, hold it to the camera level with the blue line, and click Done when it appears. | A signature that looks exactly like your pen one |
| iPhone or iPad | Click Select Device if needed, sign on the device with a finger or Apple Pencil, then tap Done. | A natural pen feel, using Continuity |
Click Clear to start any of them over. VoiceOver users can give a signature a description, such as Initials, from the Description pop-up menu before clicking Done, which helps when you keep several.
Typing on a form that won't take text
Click a field and type. If nothing happens, the PDF is a scan or a flat form with no real fields. Click Show Form Filling Toolbar, then the Text Box Tool, and click where the text belongs. The AutoFill Form button above the PDF fills names and addresses from Contacts; choose Choose Other to use someone else's details.
Preview has no date stamp, so add the date with a text box: type it in the format the form asks for, then match the font size to the rest of the line using the text style controls.
Fixing common problems
- The signature is too big or too faint. Click it to select it, then drag a corner handle. A camera signature made with a fine pen often looks faint; sign with a thicker black marker and capture it again.
- It landed on the wrong page. Select it, press Delete, scroll to the right page and click your signature in the Sign menu again.
- You need it in two places. Place it twice from the Sign menu; there's no limit on how often you use it.
- A signature you don't use anymore. Click Sign, point at it and click the X. It's removed from every Markup app on that Mac, and from your other Macs if iCloud Drive is on.
A Preview signature can be moved
Preview adds your signature as a markup on top of the page, so someone with the file can select it, move it or delete it in a PDF app. If you need the page flattened, choose File > Print, open the PDF menu in the print dialog and choose Save as PDF.
Sending it for other signatures
Preview signs for you alone. When the same PDF also needs a client's or a partner's signature, SignMaster sends it from Safari or Chrome on your Mac, and keeps a record Preview can't. Each send is an envelope: one or more documents going to one or more signers.
- 1
Upload the PDF
Click New envelope and drag the PDF in from Finder. Several PDFs can travel in one envelope.
- 2
Add everyone who signs
Click Add me to include yourself, add the others by name and email, and decide whether they sign in order or all at once.
- 3
Place the fields
Put a signature, initials and date signed field where each person signs. Date signed fills itself in when they finish.
- 4
Send
Each signer gets an email link that opens on any device. Reminders follow up for you, and everyone gets the signed PDF with a certificate of completion.
Already made a Preview signature you like? When you sign in SignMaster, you can upload a picture of your signature or take a photo of it on paper, and the paper is removed so only the ink shows.
Questions? Answers.
How do I add a signature in Preview without a trackpad?
Use Camera: sign a sheet of white paper, hold it up to the Mac's camera level with the blue line, and click Done. Or choose iPhone or iPad and sign on that device.
Can I add the date in Preview?
Yes, as text. Click Show Form Filling Toolbar, then the Text Box Tool, click on the date line and type the date. Preview doesn't stamp it automatically.
Can I keep my initials in Preview too?
Yes. Create a second signature with just your initials, the same way you made the first. Both appear in the Sign menu, so pick whichever the line asks for.
Do my Preview signatures sync between Macs?
Yes, if iCloud Drive is turned on. Signatures you create or delete on one Mac show up the same way on your other Macs that use iCloud Drive.
Sources
- Apple, Fill out and sign PDF forms in Preview on Mac · support.apple.com
- 15 U.S.C. § 7001, ESIGN Act general rule and consumer consent (govinfo) · govinfo.gov