How to Merge Multiple PDF Files
Merging is the most-used PDF operation there is: an application pack, an invoice bundle, a report plus its appendices. Doing it well is mostly about order and preparation.
Prepare before you merge
Name your files so alphabetical order matches the order you want — 01-cover.pdf, 02-report.pdf, 03-appendix.pdf. This one habit prevents most merge mistakes.
Check page orientation too. Mixing portrait and landscape sources is fine, but the reader will rotate as they scroll. Fix stray pages with Rotate PDF first.
Merging in your browser
Open Merge PDF, drop your files in, confirm the order in the list, and process. The whole operation happens locally in the page — nothing is uploaded to a server — and you get a single download at the end.
What survives the merge
Page content, embedded fonts and images carry over intact. Interactive extras are less certain: bookmarks and some annotations may not survive combining files from different producers. Check the merged file before sending anything important.
Common problems
If a file refuses to merge, it is usually password protected — open it with its password and save an unprotected copy first. If the merged file is unexpectedly huge, one of the sources is probably a high-resolution scan; run it through Compress PDF.
Frequently asked questions
How many files can I merge at once?
There is no fixed limit, but everything is held in your device's memory, so very large batches on a phone may be slow.
Can I merge only some pages of a file?
Yes — use Extract PDF Pages first to pull out the pages you need, then merge the results.