Overview
What this tool does
Merging PDFs combines two or more PDF files into a single document in the order you choose. Common reasons: combining a cover letter and a CV before sending to an employer, stitching scanned pages from a multi-part document, assembling a portfolio from individual project PDFs, joining chapters of a long report. This merger runs entirely in your browser using pdf-lib. The files you add never leave your device, never reach a server, never get cached on someone else's disk. There is no signup, no daily limit, no file-size cap (beyond what your computer's memory can handle), and no watermark on the output. The output is a fresh PDF that opens in any PDF reader.
How to
Use it in 3 steps
- Drop your PDFs onto the page (or click 'Add PDFs' to pick them).
- Reorder the files using the up/down arrows. The merged PDF follows this order top to bottom.
- Remove any file you don't want to include with the X button on its row.
- Click 'Merge & download'. The combined PDF is built in your browser and saved to your downloads folder.
FAQ
Frequently asked questions
▶Are my PDFs uploaded to your server?
No. Everything runs in your browser. We have no server that receives your files. You can disconnect from the internet after the page loads and the merge still works.
▶Is there a limit on file size or page count?
No hard limit. The merger is constrained by your device's available memory. Desktop browsers handle hundreds of pages and many large files; very large merges (1GB+) on mobile may run out of memory.
▶Does the merged PDF keep bookmarks, links, and form fields?
Page content (text, images, vectors) is preserved exactly. Page-level annotations are preserved. Document-level bookmarks and the global AcroForm are not transferred to the combined output (this is a known pdf-lib limitation; if you need bookmark preservation, use Adobe Acrobat).
▶Will the merged PDF be smaller or larger than the originals combined?
Roughly the sum of the source file sizes. The merger does not compress; if you need a smaller output, use the PDF compressor afterwards. Each source PDF is decoded and re-encoded by pdf-lib in the process, which can produce slightly smaller files if the originals had inefficient compression.
▶Can I merge password-protected PDFs?
Yes if the encryption was applied at the 'owner' permission level (the common case). Files with a strict 'user' password (the kind that prompts you to type a password to open) need to be unlocked first.