I scanned single-sided papers in duplex mode, so every second page is blank. How do I remove all the blanks at once?

Why the file came out like this

In duplex mode the scanner captures the front of each sheet and then the back, even when the back is plain white. Feed in 10 sheets printed on one side and you get a 20-page file: odd pages hold the content, even pages are empty backs. The pattern is regular, and that is what makes the cleanup quick.

How to do it

1. Open Delete PDF pages and choose the scanned file.
2. In the 'Or type the pages to delete' field, type the even pages: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20. Spaces work as separators too, so 2 4 6 8 gives the same result.
3. The matching thumbnails get a red frame straight away.
4. Scroll the grid slowly. If a back has a handwritten note or a stamp, click it to unselect it.
5. Check the summary, then press 'Delete pages and download new file'.

The tool does not detect blank pages for you

The tool does not inspect a page to decide whether it is empty. It removes only what you select. That works in your favour: a back that looks blank can carry a faint pencil signature or a pale stamp, and a tool that removed 'nearly blank' pages automatically could take it without you noticing. So the thumbnail check is not a formality.

Watch for one common case too: if one sheet in the stack was printed on both sides, its back is a real page sitting in an even position. You will not want to delete it. Click it to unselect it, and the field and the summary update together.

Check the number before downloading

• The remaining page count should equal the number of sheets you fed into the scanner. If it does not, a back was removed or kept by mistake.
• If you type a number larger than the file's page count, the field shows that the range is not valid and the thumbnails do not change until you fix it.
• Next time, choosing single-sided scanning in the scanner settings saves you this whole step.
• Your original stays as it is, and the new file's name ends in pages-removed.