Merge PDF
Add several PDFs, arrange their order, and merge them into a single document — all in your browser using pdf-lib. Your files are never uploaded.
Examples
report.pdf + appendix.pdf
combined.pdf with all pages
How it works
Add two or more PDFs, put them in order with the arrow buttons, and the pages of each file are copied, in that order, into one new document called merged.pdf.
Pages are copied as they are. Text stays selectable and images are not recompressed, so the merged file is roughly the size of the originals added together. Page sizes are kept too, which means a document that mixes A4 and Letter pages stays mixed.
Bookmarks from the original files are not carried over, and fillable form fields may stop working in the merged copy. A password-protected PDF cannot be read; remove the password first. The only limit on size is your device’s memory.
How to use Merge PDF
Why use this tool
Frequently asked questions
No. Merging happens entirely in your browser with the pdf-lib library; files never leave your device.
There is no hard limit, but very large documents use more memory since everything runs locally.
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