Merge PDF
Combine PDFs into a single document in exactly the order you want. Everything runs in this browser tab.
- No uploads
- Runs on your device
- Works offline once loaded
Select PDF files
or drag and drop here · add two or more
Processed on your device. Never uploaded.
How to use Merge PDF
- 1Choose or drop two or more PDF files.
- 2Drag the handles (or use the arrows) to put them in order.
- 3Press Merge PDF and download the result.
Merging copies every page from each document into a new PDF, keeping text selectable, links and vector graphics intact. Because the work is done by JavaScript on your device, merge speed depends on your hardware rather than your internet connection — and confidential contracts or medical records never touch a server.
Questions
Are my PDFs uploaded anywhere?
No. The files are read with your browser's File API and merged by pdf-lib running in a Web Worker on your device. You can disconnect from the internet after the page loads and merging still works.
Is there a size limit?
Up to 200 MB per file and 500 MB per merge. Very large jobs depend on your device's memory, so phones may struggle with several hundred megabytes.
Can I merge password-protected PDFs?
Not directly. Encrypted files are flagged when you add them; unlock them first and then merge.
Will bookmarks and form fields be kept?
Page content, annotations and links are kept. Document-level outlines (bookmarks) and interactive form fields from the source files may not carry over.