Merge PDF
Combine multiple PDF files into one organized document in seconds.
Drop PDFs to merge
Add 2 or more PDF files
Up to 25 MB per file · 1 file at a time on Free
About Merge PDF
Merge PDF lets you combine two or more PDF files into one organized document in seconds. Whether you’re assembling a contract from signed pages, bundling invoices for accounting, or stitching scanned chapters into a single book, the result keeps the original quality, fonts and embedded images intact. Everything happens directly in your browser, so your files are never uploaded to a server.
How to use Merge PDF
- 1
Drag and drop your PDF files into the upload area, or click ‘Choose files’ to pick them from your device.
- 2
Reorder the documents using the up and down arrows until they appear in the sequence you want.
- 3
Remove any file you no longer need with the ✕ button.
- 4
Click ‘Merge files’ and your combined PDF will download automatically — no waiting in a queue.
Why use NinjaPDF
- 100% in-browser — your files never leave your device
- Unlimited merges with no watermark or sign-up
- Preserves quality, fonts and embedded images
- Reorder pages with a single click
- Works on Windows, macOS, Linux, iOS and Android
- Open-source PDF engine you can trust
Frequently asked questions
Is it really free to merge PDFs?+
Yes. NinjaPDF’s Merge PDF tool is completely free with no daily limits, no watermarks and no account required.
Are my files uploaded to a server?+
No. All processing happens locally in your browser using WebAssembly. Your documents never leave your device.
How many PDFs can I merge at once?+
There’s no hard limit. The only constraint is your device’s available memory. Most modern laptops can comfortably merge dozens of PDFs at once.
Will merging change the quality of my PDF?+
No. Pages are copied bit-for-bit, so text stays selectable and images keep their original resolution.
Can I reorder pages before merging?+
Yes. Drag files into the order you want, or use the arrow buttons to move each item up or down before clicking Merge.