How to view, edit or remove PDF metadata on your Mac

Every PDF can carry a title, an author, a subject, keywords, the app that made it and when. On a Mac, Preview shows them in its Inspector but only lets you change the keywords. To edit or remove the title and author, use Automator's Set PDF Metadata action, which is built in, or Koi's Metadata: drag the PDF with Shift held, drop it on Metadata, change or clear any field, and save a copy.

It matters more than it looks. A PDF you send out can still name the person who wrote the first draft, the company template it came from, or the app and version that made it. One PDF we checked, saved from a web browser, listed the browser's full version string as its author.

We make Koi, so read this with that in mind. Everything about Koi here is what version 1.13 does. Preview's steps come from Apple's own guides, checked October 21, 2026, and the Automator action and Terminal command were checked on macOS 27.

1. Open the PDF in Preview.
2. Click the Info button in the toolbar, or choose Tools, then Show Inspector.
3. The General info pane shows what the PDF says about itself, such as its author, next to the file size.
4. Click the Keywords pane to see its keywords. Click Add to add one, type it and press Return, or select one and remove it.

Apple's Inspector guide describes viewing this information, and the keywords guide adding and removing keywords. Neither has a way to change the title or the author.

In Terminal, mdls Report.pdf lists what Spotlight read from the file, including kMDItemTitle, kMDItemAuthors and kMDItemCreator, the app that made it.

Automator comes with every Mac and has a Set PDF Metadata action with fields for the title, author, subject, content creator and keywords.

1. Duplicate the PDF first. Apple's own note on the action says it rewrites the whole PDF in place.
2. Open Automator from Applications, choose New Document, then Quick Action.
3. Set “Workflow receives current” to PDF files, in Finder.
4. Drag Set PDF Metadata from the Library into the workflow, and fill in the fields you want to change.
5. Choose File, then Save, and call it Set PDF Metadata.
6. In Finder, Control-click the copy and choose Quick Actions, then Set PDF Metadata.

The fields are typed into the Quick Action itself, so for a different title you open it in Automator and change it. That suits stamping the same author on many PDFs better than fixing one file.

1. Start dragging the PDF in Finder or on your desktop.
2. While you're still holding it, press and hold Shift. The PDF wheel opens round your pointer.
3. Drop the PDF on Metadata. Its first page and file details show on the left: size, pages, page size and PDF version.
4. On the right are Title, Author, Subject, Keywords, Made with, Saved by, Created and Modified. Type over any of them, or empty one to take it out.
5. Or click Remove all to take out every one.
6. Click Save copy. “Report edited.pdf” lands beside the original and shows in Finder.

• Dates are written as 2026-10-20 14:30, and Koi tells you if one isn't.
• Keywords go in one line, with commas between.
• Remove all keeps every page as it is. Only the details about the file go.
• The original is never touched. When its folder can't be written to, the copy goes to Downloads.
• A PDF a password keeps shut doesn't open.

It all runs on your Mac with Apple's PDFKit, and nothing is uploaded. Photos get the same tool on the picture wheel, for the camera, date and place a photo carries. More on the Shift wheel.

• Title: the document's name, which can differ from the file's name. Some PDF readers show it in the window's title bar.
• Author: the person or company that made it, often filled in from the account that made the first draft.
• Subject and Keywords: a line about it, and words Spotlight and Finder's search can find it by.
• Made with: the app the document was written in, like Word or Pages.
• Saved by: the software that wrote the PDF itself, often with its version.
• Created and Modified: when the PDF was made and last saved.

• Metadata isn't the pages: a name typed on a page, in a comment or in a form stays put. Check the PDF itself before you send it.
• Spotlight catches up later: mdls shows what Spotlight last read, so a changed title can take a moment to show there.
• Locked PDFs: one that needs a password to open has to be opened and saved without it first.

Just curious who made a PDF? Preview's Inspector tells you. Stamping the same author on a batch of reports? Automator's Quick Action fits. Cleaning a PDF before it goes to a client, a landlord or a journal, field by field or all at once? Koi's Metadata does it on a copy, and the same wheel compresses, reorders pages and splits PDFs.

Preview and Automator are free. Koi has no free plan: Pro is $20 a month, or $192 a year, after a 3-day free trial that needs a card. Lifetime is paid once, from $59. The Shift wheel uses no AI, so it never counts against Koi's usage. See the plans.