Merge PDFs
Combine multiple PDF files into one. All processing happens in your browser — nothing is uploaded.
Drop PDF files here
or click to browse
Multiple files supported · Max 50 MB
Common questions
How many PDFs can I merge at once?
There is no hard limit on the number of files. You can merge as many PDFs as your device's memory allows. For most users, merging 10–20 files at once works smoothly.
Will merging PDFs reduce quality?
No. pdf-lib copies pages from each document without re-encoding any content, so all text, images, and formatting are preserved exactly.
Can I merge password-protected PDFs?
Merging works with most lightly-protected PDFs. Heavily encrypted files may fail with an error. Remove the password protection first if you encounter issues.
What order will the pages appear in?
Pages appear in the order you arrange the files in the list. Use the up/down arrows to reorder files before merging.
Is it safe to merge PDFs online here?
Yes. All merging happens in your browser using pdf-lib (a JavaScript library). Your files never leave your device. You can verify this in your browser's Network tab — no file upload requests will appear.
Why merge PDFs without creating an account?
Most online PDF tools require you to create an account and upload your files to their servers — often retaining copies for days. LocalDF uses pdf-lib, a JavaScript library that runs entirely in your browser. There is no server involved, no account required, and no file retention. Your documents stay on your device from start to finish.