Note which positions are blank, then extract everything else. Removing pages 2, 4 and 6 from a ten page file means extracting 1,3,5,7-10.
Review before you delete. A scanned blank is a photograph of paper, not an empty page, and a faintly printed page can look emptier than a dirty blank one.
You scanned thirty sheets and the PDF has sixty pages. Every other one is empty. The scanner was in duplex mode, the paper was printed on one side, and it dutifully photographed the back of every sheet.
This is the most common blank page problem, and it has a tidy fix. What makes it worth more than one paragraph is that scanned blanks behave differently from the blanks in a document you typed.
A scanned blank page is not blank
When a word processor produces an empty page, that page really is empty. Its content stream draws nothing. It costs almost nothing in file size and any tool can identify it with certainty.
A scanned blank page is a photograph of a sheet of white paper. It has dust specks, paper texture, a grey shadow along the edge where the sheet did not lie flat, and often a faint ghost of whatever was printed on the other side showing through. As far as the file is concerned, that page is an image like any other.
Draws nothing. Identifiable with certainty by any tool.
A photograph of paper, with speckles, shadows and show-through.
Single-sided originals scanned in duplex produce one empty page per printed one.
Why automatic detection misfires
Tools that offer to find blank pages work by measuring how much non-white content a page has and comparing it to a threshold. That is a reasonable approach and it is not a reliable one.
It fails in both directions. A blank page from a dirty scanner bed, or one with heavy show-through from a dark page behind it, can measure above the threshold and be kept. A page containing one short line of light grey text, a page number, or a faint signature can measure below it and be deleted.
Clean, obvious cases
- Typed blank pages in a generated PDF
- Clean duplex backs from a well maintained scanner
- Consistent batches where every blank looks the same
- Documents where nothing is faintly printed
- Large batches where reviewing every page is impractical
The cases that cost you
- Pages holding only a page number or footer
- Light pencil annotations and faint signatures
- Section dividers with a single small heading
- Blanks with heavy show-through from the reverse
- Anything scanned from thin or coloured paper
Removing them safely
The method is the same as any page removal: work out what to keep and extract that. The care goes into the step before.
Look at the pages, in thumbnail view
Open the document and switch your reader to a grid of page thumbnails. Blanks are unmistakable at that size, and so are the almost-blank pages that carry a single line you would rather not lose.
Write down the positions to keep
Note the runs that survive. A duplex scan of single-sided paper is usually every odd page, which makes for a short list: 1,3,5,7,9 and so on.
Extract and check the page count
Sixty pages minus thirty blanks should be exactly thirty. If it is twenty-nine, something you wanted went with them.
Stopping it at the scanner
All of this is repair work for a problem that did not need to exist. Scanners default to duplex because it is the safe assumption for unknown paper, and most people never change it.
If the originals are printed on one side, switching the scanner to simplex removes the blanks, halves the scan time, halves the page count and halves the file size. Many scanners also have a blank page skip option that discards empty sheets during the scan rather than after it, which is better still because it never writes them in the first place.
- Duplex scan of one-sided paperSet the scanner to simplex
- Section breaks in a word processorFix before exporting to PDF
- Chapters forced to start on the rightIntentional, leave them
- Merged documents with paddingRemove after merging
- Print drivers adding separator sheetsTurn off in print settings
Drop the blank pages
Keep the pages you want and download a clean file. Runs in your browser, nothing uploaded.
Common questions
The parts that catch people out.
01Why does my scan have twice as many pages as sheets?
The scanner was in duplex mode and photographed both sides of every sheet, including the blank backs of single-sided paper. Switching the scanner to simplex prevents it, and blank page skip discards them during the scan rather than afterwards.
02Why can automatic blank detection not just find them?
It measures how much non-white content a page has and compares that to a threshold. A dirty blank can measure above it and a faintly printed page below it, so the tool keeps pages you wanted gone and deletes pages you needed. Review the result rather than trusting it.
03Does removing blank pages shrink the file?
For scanned documents, substantially. A scanned blank page is a photograph of paper and carries real file size, often 20 to 80KB each. For a PDF exported from a word processor the saving is negligible, because a typed blank page contains almost nothing.
04How do I remove them if there is no delete button?
Extract the pages you want to keep. For a duplex scan of single-sided paper that is usually every odd page, so a range like 1,3,5,7,9 and onward gives you a clean document without the blanks.
05Can I get a page back if I delete it by mistake?
From the original, yes, because the original is never modified by this operation. Keep the source file until you have confirmed the cleaned version is complete, and check the page count before you discard anything.
06Should I remove blank pages before or after merging?
Before, if the blanks came from separate scans. It is easier to spot them while the files are still small, and the file boundaries tell you which scan each page belongs to. Removing them after merging works too, it is just slower to review.