Converters / TOOLKIT
PDF Merger
Combine multiple PDF files into one document - private, fast, no uploads.
Free to use · No account needed
Local processing: 25 MiB per PDF; 64 MiB per batch. Encrypted/damaged PDFs are rejected. Page copying does not guarantee preservation of signatures, bookmarks, forms or interactive features.
How to use
Choose PDF files, then use the up/down buttons to set their order. Click Merge into one PDF and wait for the result. Use Download merged.pdf to save it. The operation keeps a fixed selection while running; changing or clearing that selection is temporarily disabled.
Use cases
Combine a two-page report A and a one-page appendix B. With A above B, the result has three pages: A1, A2, B1. Move B above A and the expected order becomes B1, A1, A2. Open the saved PDF to confirm the page content, not only its page count.
Practical tips
The limit is 25 MiB per file and 64 MiB per batch. Smaller groups may still be necessary on a phone with limited memory. Filenames do not determine order. Use a repaired or unlocked copy of your own document if the parser rejects the original.
Common mistakes
A file named .pdf can still be corrupt. On failure, the tool identifies the current file and keeps the selection for correction; remove or replace it before retrying. Adding, removing or reordering files clears the older result so you do not download output from a different selection.
Why use this tool
Document bytes are read and merged in this browser tab and are not uploaded by this tool. The result is a new page-copy document. This does not guarantee preservation of digital signatures, bookmarks, forms, accessibility tags or other interactive features; check those separately before sharing.
Frequently asked questions
Do I need more than one PDF?
What if the PDF engine fails to load?
Are my PDFs uploaded?
Will signatures and bookmarks survive?
What are the size limits?
Open-source library versions and licences · Report a reproducible issue