Merge PDF
OrganizeCombine two or more PDF files into a single document in any order. 100% private — your files never leave your browser.
How to use Merge PDF
- Open this page in any modern web browser — no download or installation required.
- Click Add file or drag and drop your PDF onto the drop zone.
- Adjust the available settings to fit your needs.
- Click the action button and save the processed file — the result is ready instantly.
Files never leave your browser. No upload to any server.
Processing runs locally on your device. No queues, no waiting.
No signup, no watermarks, no limits. Use as many times as you like.
Why use Merge PDF on PDF Modern?
PDF Modern’s merge pdf tool processes your file entirely within your web browser using modern WebAssembly technology. Unlike traditional online PDF services that require uploading your documents to remote servers, your files never leave your device — ensuring complete privacy and security. Processing happens at the full speed of your CPU, not limited by upload or download bandwidth, so even large files are handled in seconds. There are no file-size restrictions, no daily usage caps, no watermarks on output, and no account creation needed. It is a fully free, open tool built for everyday document workflows at home, school or the office.
Frequently asked questions
Is this PDF merger really free?
Yes. Unlimited use, no signup, no watermarks. The site is open source and hosted on Cloudflare Pages.
Are my files uploaded?
No. All merging happens in your browser using pdf-lib. Your files never touch a server.
Is there a file size limit?
Only your device memory. Most modern computers handle hundreds of MB easily.
Can I reorder PDFs before merging?
Yes — drag the items in the list, or use the arrow buttons to reorder.