everyday mac tools

Delete pages from a PDF on a Mac, and check they are really gone

· 6 min read

To delete pages from a PDF on a Mac, open it in Preview, choose View, Thumbnails, select the pages you want gone and press Delete. Work on a duplicate, because Preview saves the change into the file you opened. If you are removing the pages because of what is on them, rather than to tidy up, take a few extra minutes: a PDF can keep traces of deleted pages in its bookmarks, its metadata and sometimes in the file itself, and the checks below catch them.

Delete pages in Preview

  1. In Finder, select the PDF and press Command-D. Finder makes a copy with “copy” added to the name. Work on that one.
  2. Open the copy in Preview and choose View, Thumbnails, or press Option-Command-2. Every page appears in the sidebar.
  3. Click a page to select it. Shift-click to select a run of pages, or Command-click to pick pages that are not next to each other.
  4. Press Delete, or choose Edit, Delete.
  5. Scroll through what remains, then press Command-S.

Check each page at full size before deleting it. A faint scan can look blank as a thumbnail and still carry a signature, a stamp or a handwritten note.

If Delete does nothing, the PDF may have been saved with permissions that block page changes, and Preview may ask for the permissions password first. Remove the password from a PDF you own covers that case.

Deleted the wrong page? Command-Z undoes it while the file is still open. After closing, File, Revert To, Browse All Versions can usually bring back the earlier version, but the duplicate you made in step one is the reliable safety net.

Keep the pages you want instead

Sometimes it is easier to pick what stays than what goes, especially in a long document where you only need a few pages.

In Preview’s thumbnail sidebar, select the pages to keep and drag them out onto the Desktop or into a Finder window. Preview writes a new PDF containing only those pages, and the original is left untouched. Annotations and form fields on those pages come along.

For a clean, flat copy, File, Print, choose the page range, then choose Save as PDF from the PDF menu at the bottom of the dialog. Annotations and filled fields are flattened into the page, links stop working, and bookmarks are left behind. That is fine for sending a few pages of a contract and awkward for a document you still plan to edit. Split a PDF into separate files on a Mac compares these routes in more detail.

Why a deleted page is not always gone

A PDF is not a single sheet of content. It is a collection of objects (pages, fonts, images, text streams) with an index saying which ones belong to the document. The format also allows an incremental save: the app appends the changes to the end of the file and leaves the old objects where they were. After an incremental save, a deleted page is no longer listed in the index, so no viewer shows it, but its content can still be sitting in the file for anyone who reads the raw data.

You usually cannot tell from the outside which way an app saved. When it matters, make a fresh file rather than saving over the old one. Preview’s File, Export as PDF writes a new document, and so does dragging the pages you are keeping out of the sidebar. Both build the file from the pages that remain rather than adding to the old one.

The page itself is not the only place its content can live:

  • Bookmarks. A table of contents entry can outlive the page it pointed to, and its title may name the section you removed. In Preview, View, Table of Contents shows them.
  • Metadata. The title, subject and keyword fields sometimes describe the whole original document. Tools, Show Inspector in Preview displays them. Remove metadata from a PDF on a Mac explains how to clear them.
  • The pages you kept. A contents page, a running header or a line such as “see the schedule on page 14” can point straight at what is missing.
  • Page numbers. Printed numbers do not renumber themselves. A document that jumps from page 11 to page 15 tells the reader that pages were taken out.
  • Attachments and hidden layers. Some PDFs carry embedded files or layers that are not visible on the page. What a PDF still hides covers where they sit.

Check the result before you send it

  1. Count the pages in the sidebar and compare the number with what you expect.
  2. Press Command-F and search for a name or phrase that appeared only on the removed pages. If Preview finds it, it is still on a page you kept.
  3. Open View, Table of Contents and read every entry.
  4. Open Tools, Show Inspector and read the title, subject and keywords.
  5. Open the file on its own, after closing everything else, and page through it once more.

Be clear about what step 2 proves. Preview’s search looks at the pages in the document. It cannot see leftover objects that are no longer attached to any page, which is why the fresh-file step above matters more than any search.

If the content you are removing also appears on pages you need to keep, deleting pages is the wrong tool. A black box drawn over text does not remove it either; Why a black box on a PDF does not redact anything explains why, and redaction is the job you actually have.

Doing it with Basalt

Basalt is a native Mac PDF app with eighteen tools in one window. Its page tool reorders, rotates and deletes pages, and like every Basalt tool it writes a new file, so the original is never modified and the duplicate step is unnecessary. Inspect shows what a PDF still hides, and Clean Up removes layers, bookmarks and attachments.

When confidential content also runs through the pages you are keeping, Redact excises the text glyph by glyph and destroys images under a mark. You review every mark before applying, and the verifier re-opens the export with an independent parser and proves the strings are absent before any file is written. Basalt is $29 for a lifetime license on up to three Macs, and free for 24 hours with every tool.

Questions

Does deleting pages make the PDF smaller? Usually, though not always by as much as you expect. Fonts and images shared with the pages you kept stay in the file.

Can I delete pages from several PDFs at once? Not in one step in Preview. Open each file and delete the pages, or keep a folder of duplicates and work through them in turn.

Will the person I send it to know pages were removed? They can often tell from gaps in the printed page numbers or from references on the pages you kept. If that matters, fix those references before you send it.