Rotate Scanned PDF Pages Online: Fix Sideways Pages

Scanners and phone apps often save one page sideways or upside down. Rotate PDF shows thumbnails of every page so you can turn just the ones that are wrong.

Step by step

1. Open Rotate PDF and choose the file.
2. Hover (or tap) a page and press its rotate button, once for 90°, twice for 180°. Use All left / All right for every page.
3. Download.

What changes in the file

Rotation is stored as a flag on each page. In our test the output had /Rotate 90 on page 4 and 0 on the other eleven. The page content is not redrawn or re-compressed, so there is no quality loss and scans keep their text layer. All 12 bookmarks still worked.

Tips

• Fix rotation before adding page numbers or a watermark; those are placed relative to the page as it is shown.
• A few very old viewers ignore the rotation flag; if a recipient sees it sideways, ask what program they use.
• If pages are also in the wrong order, use Organize PDF, which can rotate and reorder at once.

Second round of tests: rotating everything, and rotating twice

On 28 October 2026 we ran two more checks on the live site, using a fictional 6-page report made of portrait A4 pages (3.13 MB, mostly photos) and the 12-page output from our first test.

All right on a whole document

When a whole scan came out sideways, you do not need to click every thumbnail. We pressed All right once and applied. The result screen reported “6 of 6 pages rotated”, and every page in the output had /Rotate 90. The file size barely moved (3.13 MB in, 2.99 MB reported on the result screen), which matches what you would expect when only a page flag changes and the photos are not re-encoded. Use All left instead if the tops of the pages point to the right.

Rotating a page that was already rotated

We opened our earlier output, where page 4 already had /Rotate 90, and rotated page 4 once more. The new file had /Rotate 180 on page 4 and 0 everywhere else, so the rotation adds to what is already in the file rather than starting from zero. This is useful when a file has been “fixed” once in the wrong direction: one more quarter-turn in the same direction, or one in the other direction, gets it upright without starting over from the original scan. All 12 bookmarks were still in the output.

A quick checklist before you send it

• Look at the thumbnails after rotating: the preview shows each page the way a viewer will show it.
• If only some pages are wrong, rotate those one by one instead of using All left/All right.
• Because the change is a page flag, you can rotate the same file again later without any quality loss.

How we tested this

Date	22 October 2026
Environment	Google Chrome 155 (headless) on Linux x86_64, desktop viewport 1280×900, PDFroo build of 22 October 2026
Test file	Fictional 12-page report with 12 bookmarks
Settings	Page 4 rotated once
Results	/Rotate 90 on page 4 only; bookmarks kept
Network	The browser made no request that carried the file: the only requests during processing were same-origin page prefetches and local blob: URLs.
Re-test	28 October 2026 on the live site: All right on a 6-page file (6 of 6 pages /Rotate 90); page 4 of a file that already had /Rotate 90 turned again (/Rotate 180, bookmarks kept)

During these runs the only POST requests went to the site’s analytics endpoints (Cloudflare Web Analytics and Google Analytics); no request went to a PDFroo processing server, and the result was produced in the browser.

We checked every output with pypdf, pdfinfo and pdftotext, and recorded every network request the page made while the file was processed. See our tool testing methodology.