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How do I rotate all 400 pages of a scanned book without waiting for every thumbnail?

Choose 'All pages' and press the rotation you need. You do not have to select anything or wait for the thumbnails to finish. Export does not redraw the scanned images; it changes each page's rotation value and saves the file. The tested limit is 500 pages and 100 MB per file.

Published · 3 min read

Why the whole book came out sideways

When you scan a book with a phone app or a flatbed, you usually lay it landscape so both pages fit or because the spine only sits flat that way. Every page then comes out on its side in the same direction. The good news is that the error is regular: every page needs the same turn, which is exactly what the 'All pages' option is for.

The steps

  1. Open Rotate PDF pages and choose the file. Wait only until the page count appears.
  2. Make sure 'Apply rotation to' is set to 'All pages', which is the default whenever a file opens.
  3. Look at the first thumbnail that appears to see which way the pages face, then press 'Right 90°' or 'Left 90°'.
  4. Check the summary, then press 'Download rotated PDF'.
Worked example

A scanned book of 400 pages, where the top of every page points right.

You press 'Left 90°' with 'All pages', and the summary shows: Pages that will be rotated: 400 of 400, and 270° clockwise: pages 1-400.

Every page with a value of 0 becomes 270 in the exported file.

Why you need not wait for the thumbnails

Drawing 400 thumbnails of scanned pages takes time, especially on a phone, and the progress bar shows it. But the tool knows the page count from the moment the file opens, and a rotation button with 'All pages' applies the angle to every page at once. Thumbnails not drawn yet will appear already rotated when they finish.

Why export is quicker than with other tools

The tool does not open the scanned image on each page or recompress it. It changes one number in each page's description and saves the file. Compared with a tool that redraws every page as a picture, that is much lighter, and quality does not change. Saving a large file still needs memory, though, because the browser holds the whole file, so close other tabs on a phone.

Cases worth watching

  • A few pages that differ, such as a cover you scanned portrait: after rotating everything, choose 'Selected pages', select the cover and press the opposite button, which returns it to its original orientation. In the book example the summary then reads: 270° clockwise: pages 2-400.
  • A book over 500 pages or 100 MB: it is past the tested limit and the tool refuses it, so save it as two parts from the scanning app itself and rotate each part.
  • The tool turns in right angles only, so it does not straighten pages that are slightly skewed from the curve of the book during scanning.

Common questions

Do I need to click every page or type 1-400?

No. 'All pages' is enough. Typing in the field is only needed when you want some pages and not others.

Does the file size change?

Hardly, because the scanned images stay as they are. The size may differ slightly only because the file is saved again.