How to Merge PDFs in the Right Order
To combine several PDFs into one, open the merge tool, select all the files, arrange them in the list and download merged.pdf. The files are assembled in your browser and never uploaded.
When merging is actually the right move
A client or a portal accepts a single PDF, and you have a contract, its attachments and a signed scan to submit together. Merging is the last step before sending, and it is more reliable than asking the recipient to open files in the right order.
Phone-scanned pages, chapters exported from different apps, and files produced by a scanner app often need to become one document for printing or email. If two pages end up in the wrong order, you can fix that in the list instead of rescanning.
- A submission form allows only one upload.
- Contract, annexes and signature page need binding order.
- Loose chapters should print as one document.
How to avoid the usual mistakes
The list order is the output order. Use the ↑ and ↓ buttons or drag an item to move it, and remove duplicates with ×. Before merging, check the page count and orientation of each file; mixed portrait and landscape scans are where surprises show up. An encrypted PDF is marked as failed and skipped while the rest continue, so compare the final page count with what you expected.
Only page content is copied. Bookmarks, outlines, form fields and digital signatures are not carried over. If a signed contract must keep its signature valid, do not merge it to change page order — re-sign the final file instead. Very large scans can exhaust memory on a phone, so split the job if needed. Everything runs locally; closing the page clears the files.
- Check page counts and orientation before merging.
- Save encrypted PDFs as unlocked copies first.
- If forms or signatures matter, merge in the original app instead.
- The output should contain the sum of all page counts; a shortfall means a file was skipped.
When not to merge
If you only need a few pages from one PDF, use Extract Pages; merging cannot remove pages. If you need several files out of one, use Split. When bookmarks, outlines, AcroForm fields or a digital signature must survive, merging will drop them; use a desktop PDF editor that preserves those structures.
If your source material is images rather than PDFs, turn the images into a PDF first, then merge. Merging does not compress scans either: several large files will still produce a large file, so handle compression separately.
- Keep or drop pages: use Extract.
- One file into many: use Split.
- Image sources: convert to PDF first.
- Bookmarks, forms or signatures: use the original editor.
FAQ
Are bookmarks, forms and signatures preserved when merging PDFs?
No. The tool copies pages into a new document, so bookmarks, outlines, form fields and digital signatures are lost. A signed file must be signed again after merging.
Why does one PDF refuse to merge?
Usually it is encrypted with an open password, which the tool cannot decrypt; it will be marked as failed and skipped. A damaged file, or a .pdf that is really an image with the wrong extension, can fail the same way. Save an unlocked copy in the original app and try again.
How do I change the merge order, and does it work on a phone?
The list order is the merge order. Drag an item or use the ↑ and ↓ buttons, and remove files with ×. Mobile browsers work too, but very large scans may run out of memory, so add fewer files at a time.
Related tool：Merge PDF