How to use the find duplicate pages in pdf
- Choose a PDF (up to 25 MB and 500 pages). Text is read from each page.
- Choose how to compare: ignore upper and lower case, and ignore stand-alone numbers such as page numbers and dates.
- Read the groups of identical pages. Each group lists its pages and a preview of the shared text. Pages with no text are listed separately.
- Choose Download without duplicate pages to save a copy that keeps the first page of each group.
How pages are compared
Each page is read with pdf.js, which returns the text with its position. The text of a page is cleaned by collapsing spaces and, if you choose, by lowercasing it and removing numbers that stand alone. Two pages are duplicates when their cleaned text is exactly equal. The first page of each group is kept and later copies are dropped, in the original order. In a test file with pages "Alpha report", "Beta", "ALPHA report", "Gamma 7", "Gamma 8" and a blank page, ignoring case and numbers finds two groups, pages 1 and 3, and pages 4 and 5, and keeps pages 1, 2, 4 and 6.
This is a text comparison. A scanned page has no text layer, so it cannot be compared and is always kept, and the page lists those pages so you can see them. Pages that look the same but differ in the text layer, or look different but have the same text, are treated by their text only. To compare two files page by page, with images, use the compare PDF tool.
Common uses and cautions
Scanned-and-merged packets, exported reports with repeated cover sheets, and mail-merged documents are common sources of repeated pages. Decide whether a repeat is truly a duplicate before you drop it: two pages with the same text but a different signature image would still be counted as equal. The original file is not changed, and the new file contains copies of the kept pages.
To remove blank pages, use the remove blank pages tool; to join files, merge PDF; and to split one, split PDF. The file is read in your browser, and nothing is uploaded.
Assumptions and limits
- The PDF has a text layer. Scanned images without text are not compared.
- Text is compared after spaces are collapsed. Hyphenation and line breaks that change the text make pages differ.
- Encrypted PDFs cannot be opened. Remove the password in the program that made the file.
- Form fields and annotations are copied with the pages, but links between pages may break when pages are dropped.
Frequently asked questions
Why are two identical-looking pages not grouped?
They may differ in a small piece of text, such as a number, or one may be a scan without a text layer. Tick the option to ignore numbers, or compare the files with the compare PDF tool.
Does it delete anything from my original file?
No. The original is not changed. The tool saves a new PDF with the pages you keep, and you choose whether to use it.
What does ignoring numbers do?
It removes words that are only digits and punctuation, such as 3, 10/12 or 1,200, before comparing. It lets pages that differ only by a page number or date count as duplicates.
Which copy is kept?
The first page of each group, in the original order. The later copies are removed. If you want a different copy, split the file with the split PDF tool instead.