How to sign a PDF on a Mac (Preview or the browser, both local)

Macs can already sign PDFs locally with Preview, and for a basic trackpad signature it's a fine choice. The free in-browser signer is the alternative when you want typed handwriting styles, a photographed signature with the background removed, or a guaranteed flattened output, still with no upload and no install.

Last verified: July 17, 2026

Sign a PDF free, no upload

Sign a PDF in the browser on your Mac

  1. 1

    Open the signer in Safari or Chrome

    Click Choose file and pick the PDF, or drag the file from Finder straight onto the page. It loads locally, nothing is transmitted.

  2. 2

    Create your signature

    Draw with the trackpad or mouse, type your name in a handwriting font, or hold your paper signature up to the webcam, the background is stripped automatically.

  3. 3

    Place and adjust

    Drag the signature where it belongs, resize with the handles, add more fields on other pages if needed.

  4. 4

    Download the flattened PDF

    The signed file saves to your Downloads folder with the signature permanently flattened into the page, it can't be nudged or lifted in another viewer.

Mac specifics worth knowing

  • When Preview is enough

    Preview's Markup (Tools → Annotate → Signature) captures a signature by trackpad or camera and keeps everything local. If you sign the same way every time on this one Mac and a movable annotation is acceptable, use it, it's built in and free.

  • When the browser signer is better

    Typed handwriting styles, photographed signatures with automatic background removal, output flattened into the page rather than layered on top, and the identical flow on any machine, including the locked-down work Mac where you can't add anything to Preview's trust settings or install helpers.

  • Same page, same guarantee

    Like Preview, the signer keeps the document on your machine, the difference from typical web PDF tools. Disconnect from the network after loading and the whole flow still works.

Frequently asked questions

Is signing in the browser as private as using Preview?
Yes, in the way that matters: in both cases the document stays on your Mac. The signer runs entirely in the browser page, no upload, no account, which you can verify by signing while disconnected from the internet.
Why would I flatten a signature into the PDF?
A flattened signature is part of the page image, so it can't be selected, moved, or deleted in another PDF viewer, and it prints exactly as placed. Annotation-layer signatures (like Preview's) can be lifted or shifted by other software.
Does this work the same in Safari, Chrome, and Firefox?
Yes. It's standard web technology, so the flow is identical in any modern macOS browser, pick whichever you already use.

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Sign a PDF free, no upload
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