Merge PDF Files Online — Combine Multiple PDFs Into One_
Combine two or more PDF files into a single document in seconds. Drag to reorder, merge unlimited files with no size cap — free, no upload, no watermark, no sign-up.
Merging adds, it does not compress. The output is roughly the sum of the inputs because every page is carried over at full quality. People often expect a merge to also shrink things and are surprised by a 60 MB result. That is correct behaviour — you would not want a merge silently degrading your scans. If the combined file is too big to email, compress it as a separate second step.
Order is set before you merge, not after. The on-screen order is the page order in the finished document. There is deliberately no automatic alphabetical sort, because filename order and intended reading order disagree far more often than they agree — camera and scanner filenames especially.
What happens to links and form fields. Page content, text and images always survive. Bookmarks are commonly dropped, internal links can end up pointing at the wrong page once everything is renumbered, and form fields may collide when two source documents use the same field names. Visual documents merge cleanly; interactive forms deserve a check.