PDF Merge
Combine multiple PDF files into a single document — entirely in your browser. Drag and drop your PDFs, reorder them with the arrow buttons, and download the merged result. Your files never leave your device.
How to use
- 1
Add your PDFs
Drag and drop one or more PDF files onto the dropzone, or click to browse. You can add files in batches — they will all be queued.
- 2
Reorder the pages
Use the up and down arrows next to each file to set the order in which they will appear in the merged document. Remove any file with the × button.
- 3
Merge
Click the Merge button. pdf-lib reads each file in your browser memory, copies every page into a new combined document, and writes the result as a fresh PDF.
- 4
Download
Click the download button to save the merged PDF. The original files are never uploaded — everything happens locally.
Common use cases
- Combine scanned receipts and invoices into a single expense report.
- Merge a cover letter, résumé and portfolio into one application PDF.
- Join chapter PDFs into a complete e-book or report.
- Concatenate multiple contract sections signed by different parties.
Limitations
- Files larger than 100 MB may take several seconds to process and use significant memory.
- Encrypted or password-protected PDFs cannot be merged — remove the password first.
- Interactive form fields, annotations and bookmarks from the source files are not preserved in the merged output.
- The output file name is derived from the first file in the list; rename it after download if needed.