Live free online PDF tool

Merge PDF files online

Combine multiple PDFs, keep the order you choose, optionally add duplex blanks and normalize pages to A4. PDF Help is fast, free and privacy-conscious.

No sign-up for core toolsAutomatic deletionClean workflow
A4 scales each page proportionally and centers it on an A4 page.
Merge PDF · 2-20 files · max 50 MB each

How to use this tool

  1. Choose files or drop them into the upload box.
  2. Review the options and start processing.
  3. Download the result before the temporary link expires.

Uploads and generated files are stored temporarily only. Temporary job and download URLs are not intended for indexing.

Options and output

  • Arrange uploaded files before merging.
  • Keep mixed page sizes or normalize output to A4.
  • Add blank pages between documents for duplex printing.

FAQ

Is Merge PDF free to use?

Yes. PDF Help is ad-funded and keeps core PDF tools free without requiring sign-up.

What happens to my files?

Files are uploaded for processing, stored temporarily, and automatically deleted after the short job expiry window.

Can I use it on mobile?

Yes. The upload flow and tool pages are designed for desktop and mobile browsers.