Merge PDF Files Online
Merge multiple PDF files into one document in the exact order you choose. Processing runs locally in your browser.
Written by Anil Gautam · Updated
In what order does Merge PDF join the files?
Files are joined top to bottom, in the order of the Merge order list. Each file you add goes to the bottom of the list, so you can add files in several rounds, and anything that is not a PDF is ignored. Next to each name the list shows the file size, which helps tell two similar scans apart. The up and down arrows swap a file with its neighbour, the x button removes it, and the merge button stays disabled until two files are listed. Adding the same file twice repeats its pages.
If A.pdf has 3 pages, B.pdf has 5 and C.pdf has 2, the order A, B, C gives a 10-page file: A fills pages 1 to 3, B pages 4 to 8 and C pages 9 and 10. Press the up arrow on C twice and it moves to the top, so its pages become 1 and 2 and A starts on page 3. The download is always called merged.pdf, so rename it before merging another set.
What carries over into the merged PDF?
Pages are copied as they are, each with its own size and orientation, so an A4 page and a Letter page sit next to each other without being resized. Images and page content are copied without recompression, and the merged file is roughly as large as the inputs added together; run Compress PDF afterwards if a portal limits the size. Only pages are copied. Bookmarks, the document title and other file-level settings from the sources are left behind.
Why are some merged pages blank?
Pages from a password-protected PDF come out blank or unreadable. The merge reads encrypted files without decrypting them, and no error appears. That includes files that open without asking for a password but carry editing restrictions, so page through the result before you send it. For Aadhaar and bank statement PDFs, the matching password remover on OneClickUse makes an unprotected copy you can merge. If nothing downloads after you press merge, one of the files could not be read as a PDF; remove files one at a time to find it.
Merge PDF moves whole files, so reordering pages inside one file takes a split first. For a 6-page file whose page 5 must come first, type 5, 1-4, 6 in Split PDF, then merge split-01.pdf, split-02.pdf and split-03.pdf in that order. Photos and scans can join the set after JPG to PDF turns them into a PDF.