Remove Blank Pages from PDF

Double-sided scanning of single-sided originals leaves an empty page after every printed one, and exported reports often contain stray blank pages. This tool looks at every page, measures how much of it is covered with ink, and removes the pages that are blank — including near-blank scans with a little dust or a faint shadow, depending on the sensitivity you choose. The pages you keep are copied unchanged, and nothing is uploaded.

How to use this tool

1. Drop the PDF (or several).
2. Keep the default 0.1% for clean digital files; raise it to 0.3–1% for scans with specks.
3. Tick "Ignore a 5% border" if scanner edges, punch holes or lone page numbers should not count.
4. Use "Preview only" to see the ink % of every page first, then create the cleaned PDF.

Formula

Ink % = pixels with brightness < 235 ÷ all pixels × 100; a page is blank when ink % ≤ the threshold

Brightness is 0.299 R + 0.587 G + 0.114 B on a 0–255 scale, so anything clearly darker than white paper counts as ink, including light gray text. Pages are rendered at 40 DPI for speed (an A4 page is about 330 × 470 pixels) or 72 DPI for very small marks. One full-width line of 12 pt text covers roughly 0.4–0.6% of an A4 page.

Example

A 20-page scan of single-sided letters scanned double-sided: the 10 printed pages show 3–9% ink, the 10 backs show 0.01–0.06% because of dust. With the default 0.1% threshold all 10 backs are removed and the result has 10 pages.