Open the PDF, tilt your head. You rotate the view, scroll down — and the next page goes sideways again. Whoever scanned this fed it in the wrong way.
The rotation lives inside the file. View-rotation in your reader doesn't save. You need to rotate the pages and rewrite the document.
What's actually going wrong
PDFs store each page's orientation as metadata. A page that displays sideways has its rotation set to 90 or 270 degrees, either because it was scanned that way or because the source app misread the page orientation at export.
Most viewers offer a View > Rotate command, but it only rotates the on-screen display. The next person who opens the file sees it sideways again. To fix it for everyone, you need to permanently rotate the page data.
The quick fix
Drop the file into rotate PDF pages. Pick the pages that are wrong (or rotate all, if every page is sideways), choose the direction, save. Done — the file is now correctly oriented for every viewer, every device, forever.
If only specific pages are wrong, Flint's page picker lets you rotate selectively. The rest of the document stays untouched.
If that didn't work
Some PDFs combine page rotation with content rotation — the page is the right way up but the text on it is rotated. That's harder. The text is essentially a sideways image on a portrait page. Use convert PDF to JPG, rotate each image, then convert image to PDF to rebuild.
For scanned documents where every alternate page is rotated, set up a scan profile that auto-rotates based on text orientation. Most modern scanners support this.
Prevent it next time
When scanning, check the first page before scanning the rest of the stack. Enable auto-rotate on your scanner if it has it. When exporting from a source app, double-check landscape pages were exported as landscape rather than rotated portrait.
FAQ
Why does my PDF rotate back when I save it?
Your viewer is rotating the display, not the file. Use a tool like Flint's rotate PDF pages, which rewrites the page rotation metadata permanently.
Can I rotate just one page?
Yes. Flint's page picker lets you select individual pages or ranges and rotate only those, leaving the rest of the document alone.
Will rotating a PDF affect its quality?
No. Rotation changes metadata, not content. The page data stays untouched; only the displayed orientation changes. There's no quality loss.
Why are odd pages portrait and even pages landscape?
Common with duplex scanners that flip alternating pages. Rotate the affected pages in Flint, or rescan with the auto-rotate setting on.
Tilting your head isn't a fix. Rotate PDF pages in Flint and save the file the way it should display — for you and everyone else.