How to remove duplicate pages from a PDF: a step-by-step guide
Cập nhật 2 tháng 10, 2026
Hướng dẫn này chưa có bằng tiếng Việt nên được hiển thị bằng tiếng Anh. Bản thân công cụ có tiếng Việt.
A sheet scanned twice, the same attachment merged into a file again, a page copied by hand: Remove duplicate pages from PDF compares every page with the ones before it as the file loads and marks each repeat for removal. The first occurrence always stays, and you check every mark before anything is deleted. It all happens in your browser; nothing is uploaded.
Dùng thử miễn phí, không cần đăng ký: tệp của bạn không bao giờ rời khỏi thiết bị.
Tóm tắt
- Drop your PDFs on the page, or press Add files.
- Check the pages marked Delete - each says which page it repeats.
- Click a page to keep it, or to remove one the tool missed.
- Press Remove duplicate pages: the cleaned file is saved to your device straight away.
Add the files
Drop the PDFs anywhere on the page, or press Add files. Every page is read on arrival - the file list counts the duplicates of each file. The repeats are marked for removal, each with a badge naming the page it repeats; the first occurrence is never marked.

What counts as the same page
A page with text is compared by its text: the same text is a repeat however it was rendered, and different text - one changed figure on an invoice - is never one, however alike the pages look. A scan without text is compared by its look, and What counts as the same page decides how alike:
- Exact - only an identical repeat, the same file merged in twice;
- Normal (the default) - the same sheet scanned again: noise, a slight skew or another exposure still count as the same page;
- Loose - a rescan on another day or another scanner, a copy of a copy; check the marks, a look-alike form page may slip in.

The pages are read once; a change of setting re-judges them at once. A blank page is never matched - Remove blank pages from PDF is for those.
Decide page by page
A click on a page changes its fate: a marked page is kept, an unmarked one is removed; Shift + click marks a run, and the field above the thumbnails takes page numbers. Your own marks stay when the setting changes. Back to detected drops them, Read again reads every page anew.
Remove and save
Press Remove duplicate pages. The line under the button counts the pages that go. The cleaned file is saved to your device at once - several files together as a ZIP. Bookmarks and links of the pages that stay are kept, and the removed pages are gone from the file, not only hidden.
Limits
Without an account, and with a free one, you can clean two files in a run, each up to 15 MB. With Pro there is no limit on the number or the size.
What next?
- Empty pages from a duplex scan? Remove blank pages from PDF.
- Pick other pages to remove? Delete Pages.
- Two versions to tell apart? Compare PDFs.
Sẵn sàng thử chưa?
Dùng thử miễn phí, không cần đăng ký: tệp của bạn không bao giờ rời khỏi thiết bị.
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