Merge PDF
Combine PDFs in a precise order and keep every page from the source files.
Your files stay on your device. Nothing is uploaded.
Supported formats
- Input: PDF
- Output: one merged PDF
- 2 to 20 PDF files
Limits and behavior
- Each PDF can be up to 100 MB, with a 200 MB total limit.
- Encrypted or corrupt PDFs are rejected with an explicit error.
- The output page count must equal the sum of the inputs, or no file is produced.
- Digital signatures may not remain valid after merging.
Processed on your device
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How to merge PDFs
- 01
Choose two or more PDF files.
- 02
Drag or use the arrow buttons to set the order.
- 03
Merge and download the combined PDF.
PDF merge questions
Will any pages be dropped?
No. The output page count equals the sum of all input page counts, or the merge fails without producing a file.
Can I merge encrypted PDFs?
No. Remove the password first, then try again. Encrypted files are reported instead of being skipped silently.
How many PDFs can I merge?
Between 2 and 20 files. Each file can be up to 100 MB, and the total must stay at or below 200 MB.
Are digital signatures preserved?
Not guaranteed. Merging creates a new document, so existing signatures should be treated as invalid on the result.
Are my PDFs uploaded?
No. Merging runs locally with pdf-lib and makes no network requests.