Merge PDF files online
Merging PDFs is an everyday task: building an application package, grouping the month’s invoices, assembling a contract with its exhibits, joining the chapters of a thesis. Drop 2 to 20 files, arrange them in the order you need and get a single document whose pages are assembled without recompression — the visual quality stays identical to the sources. Unlike online services that require sending your documents to their servers, all processing runs in your browser: a contract or a bank statement never passes through a third-party machine. Combine PDFs to prepare a complete file as one attachment, gather the pieces of a single case or produce one document to archive — no software to install, no account to create.
FAQ
Does merging send my documents over the internet?
No. Files are read and assembled by your browser, on your device. You can check in the developer tools (Network tab): no request carries the content of your PDFs.
How many files can I combine, and up to what size?
From 2 to 20 files per operation, 50 MB total. Beyond that, merge in batches then combine the results.
Can a password-protected PDF be merged?
Not directly: encryption blocks page reading. Unlock it first with the “Unlock PDF” tool, then add the resulting copy to the merge.
Are quality and bookmarks preserved?
Pages are copied as-is, with no image re-encoding or loss of sharpness. Bookmarks are rebuilt in the merged file — chapter navigation is preserved. Honest limit: form fields do not carry over as a unified form — flatten them first if the result must stay reliable.
Can I interleave the pages of two documents?
Merging concatenates whole files in the chosen order. To alternate page by page (fronts and backs scanned separately), use the “Interleave two PDFs” tool.
Can I merge PDFs of different page sizes (A4, Letter)?
Yes — each page keeps its original size in the combined document; different sizes coexist without issue. To unify them, run “Resize pages” afterwards.
Should I flatten fillable forms before merging?
Recommended when the documents share field names: in a merged PDF, two identically named fields mirror each other’s value. Flatten each form first with “Flatten a PDF” and every document keeps its own answers.
Can I mix scanned and native PDFs?
Yes — each page keeps its nature in the merged document: scan pages stay images, native pages keep selectable text and vectors. The result simply combines both without any conversion.
What if a file is rejected when I add it?
Check that it is an unencrypted PDF within the size limit. A damaged file that a reader still opens can often be salvaged: run it through “Repair a PDF” first, then merge the repaired copy.
What order do the pages follow in the merged file?
The order you set by dragging the thumbnails before merging — files and their pages are concatenated in that sequence. To rearrange afterwards, run the result through “Organize pages”.
More than 20 files or 50 MB to combine?
Work in batches: merge a first group, download it, then merge that result with the next group. The final document has no practical limit on page count — only each operation is capped.
How to proceed
- Drop your PDF files into the upload area (2 to 20 files, 50 MB total)
- Drag the thumbnails to set the final document order
- Click “Merge” then download the combined PDF
- Preview the pages before downloading the final PDF