How merging works
Pages are copied from each PDF into a new document without being re-rendered, so text stays sharp, selectable and searchable, and the merged file is roughly the size of the originals added together.
Interactive extras such as fillable form fields and bookmarks may not carry over — the visible page content always does.
We tested it: three PDFs into one
We merged a 19-page text PDF, a 9-page photo report and an 8-page scan:
| Input | Pages | Size |
|---|---|---|
| Text handbook | 19 | 100 KB |
| Report with photos | 9 | 2.31 MB |
| Scanned contract | 8 | 9.49 MB |
| Merged result | 36 | 11.84 MB |
The merge took 0.2 seconds, and the result is slightly smaller than the three files added together, since shared structure is stored once. Pages, text and images are copied exactly, with nothing re-compressed.
Need it under a portal limit? Compress the merged file afterwards with Compress PDF to 2 MB or 1 MB.
When you'd merge PDFs
- An application portal accepts only one file but you have several documents.
- Putting a cover letter, CV and certificates into one submission.
- Combining monthly statements or invoices for your records.
If the result is too large
Merging adds the sizes together. If the final PDF is over a portal's limit, use Compress PDF to 1MB or Compress PDF to 2MB on the merged file.
Frequently asked questions
Can I choose the order?
Yes. Use the arrows to move each file up or down before merging.
Can I merge password-protected PDFs?
Remove the password in a PDF reader first; locked files can't be opened here.
Will the quality change?
No. Pages are copied as-is, not re-rendered.