How to rotate a PDF on a Mac (and keep it rotated)

With PDF Unlimited (free)

1. Open Pages mode

   Open the PDF in PDF Unlimited and click Pages in the toolbar mode switcher.

2. Select the pages

   Click the sideways page. ⌘-click to add more, or select every page if the whole document is turned.

3. Rotate

   Rotate the selection left or right. Repeat until the pages are upright.

4. Save

   Save the PDF. The new orientation is written into the file, not just your view of it.

With Preview, built into macOS

1. Show thumbnails

   Open the PDF in Preview and choose View > Thumbnails, or View > Contact Sheet.

2. Select and rotate

   Select the pages to turn, then choose Tools > Rotate Left (⌘L) or Rotate Right (⌘R). The toolbar rotate button works too; hold Option to rotate the other way.

3. Save

   Choose File > Save, or close the window. Preview saves changes automatically.

Why rotation sometimes does not stick

If a PDF goes back to sideways, it is usually one of these:

• A view-only rotate. Some PDF readers have a rotate view command that only changes what you see on screen and is never saved. Rotate the pages themselves, as above, and save.
• It was never saved. Files opened from an email preview or a read-only folder may not accept changes. Save a copy somewhere you own, like Documents.
• An old thumbnail. The Finder or Quick Look can show a cached thumbnail for a moment. Open the file to check.
• The wrong copy. If you exported a new file, make sure you are sending that one, not the original.

One page or the whole document

Scanned documents often have one landscape page, like a wide table, in a stack of portrait pages. Rotate just that page. Phone scans sometimes come in entirely upside down; select all pages and rotate twice.

While you are in Pages mode, you can also delete pages you do not need, reorder them, or crop the margins.

Rotating does not change quality

Rotation turns whole pages by 90-degree steps. Text, images and annotations stay exactly as sharp as before, and the file size barely changes.

If a document will be read on screen, upright pages also help OCR: text recognition works best on pages that are the right way up.

Why scans come in sideways

Scanners and phone scanning apps guess which way is up, and they often guess wrong on landscape pages, receipts and anything with little text. Fixing it before you send the file saves the reader from tilting their head, and keeps every page facing the same way when the PDF is printed.

A quick habit: after scanning, open the file in Pages mode and scan the thumbnail grid for anything sideways. It takes seconds and catches upside-down pages too.

Questions