Why are my PDF pages sideways?
Scanners and phone scanning apps don't always detect which way a page faces, especially for landscape tables, forms with little text, or pages fed upside down. Documents assembled from different sources can also mix portrait and landscape pages, and some apps export landscape pages rotated by 90°.
Turning the view in a PDF reader only fixes it for you, for this session. The person you send the file to sees it sideways again.
A permanent, lossless fix
Every PDF page has a rotation setting that tells viewers how to display it: 0, 90, 180 or 270 degrees. This tool changes that setting on the pages you choose and saves a new PDF. Every viewer (Adobe Acrobat, Preview, Chrome, Edge, phone readers) honours it, so the pages open the right way up everywhere and print correctly.
Because only the rotation setting changes, the content isn't touched: text stays selectable, scans keep their full resolution, and the file size stays almost exactly the same.
Rotating only some pages
Leave the page box empty to rotate the whole document, or list the pages that need turning, for example 3, 7-9 for a report with a few landscape tables. Ranges work the same way as in Split PDF: 5- means page 5 to the end, and -2 means the first two pages.
Rotations add up: a page already displayed at 90° and turned another 90° right ends up at 180°. If a page comes out the wrong way, run the new file through again with 90° left to undo it.
Which direction should I rotate?
Look at how the page appears in a PDF viewer now:
- 90° right (clockwise): the top of the text is on the left side of the page.
- 90° left (anticlockwise): the top of the text is on the right side.
- 180°: the page is upside down.
Private and free
The PDF is processed in your browser with pdf-lib and never leaves your device. Signed PDFs will show the signature as invalid after any change, rotation included, so rotate before signing. Password-protected PDFs need the protection removed first.
Why doesn't rotating in my PDF reader stick?
Most PDF readers have a rotate button, but in many of them it only rotates the view. In Chrome's built-in viewer and in Adobe Acrobat Reader's View → Rotate View, the change disappears when you close the file and isn't saved for anyone you send it to. Saving a rotation in Acrobat needs Acrobat Pro's page tools. Preview on a Mac does save rotations, which is one of the few built-in exceptions.
This tool writes the rotation into the file, so it's permanent and works in every reader.
Printing documents with mixed orientation
When a document mixes portrait pages with landscape tables, you might not need to rotate anything for printing. Most print dialogs, including Acrobat's 'Auto portrait/landscape' and Chrome's default layout handling, rotate landscape pages to fit the paper automatically. Rotating matters for reading on screen and for sending, where the reader sees each page exactly as stored.
Getting scans the right way up
To avoid rotating later, check your scanner's paper-feed icon, which shows which edge goes in first and whether pages go face up or down. Many scanner and phone-scanning apps also have an auto-orientation option that detects the direction of the text on each page; turning it on catches most sideways pages. It struggles with pages that have very little text, like photos or signature pages, which is when a quick fix here comes in handy.
How do I rotate a PDF on iPhone or Android?
On iPhone and iPad, the Files app has quick rotate actions: press and hold a PDF, choose Quick Actions, then Rotate Left or Rotate Right. That turns every page of the document. To rotate only some pages, open this page in Safari instead and list the pages to turn. Android has no built-in way to rotate and save a PDF, so a browser tool is the simplest option there. Either way, the rotated file is saved as a new PDF and the original stays untouched. On a computer, the same applies: your original is never modified, so if you pick the wrong direction you can simply start again from it, or run the new file through once more with the opposite rotation.