Merge PDF
Combine multiple PDFs into one in the order shown
No PDFs yet — pick two or more files above.
Why merge PDFs in the browser?
Online PDF mergers from search-engine ads usually upload your file to a remote server, process it, and offer the result for download. That works for non-sensitive PDFs but is risky for anything confidential — contracts, financial statements, medical records, internal reports.
This tool uses `pdf-lib` to merge entirely in your browser. Files never leave your device; nothing is logged on our server. The merge preserves each source PDF's pages in order; bookmarks and metadata of the first PDF are kept on the merged result.
Common use cases
- Combine a contract's main body and signed signature page into one final PDF.
- Bundle weekly reports into a single archive for end-of-month review.
- Merge invoices from multiple vendors into one PDF before submitting expenses.
- Combine PDF chapters into a single book file for an e-reader.
Frequently asked questions
How big can the merged PDF be?
Limited by browser memory. Combining several hundred MB of PDFs may slow the browser; for very large jobs, a desktop tool (qpdf, PDFsam) is more efficient.
Are bookmarks preserved?
Bookmarks of the first PDF are preserved; subsequent PDFs' bookmarks are dropped (a `pdf-lib` limitation). The page order itself is preserved exactly.
Can I reorder PDFs before merging?
Yes — drag PDFs in the list to set the order. The merged file follows the list order top to bottom.
Will the merged PDF be larger than the sum of the parts?
Slightly larger due to PDF metadata overhead, but the difference is usually under 1%. Pages are NOT recompressed during merge.
Are my PDFs uploaded?
No. Merging happens entirely in your browser — neither source files nor the merged result leave your device.