About PDF-M

PDF-M does one job and tries to do it better than anyone: combining PDF files into one document, quickly, for free, without asking you to upload anything.

How it works

Most online PDF tools upload your documents to their servers, process them there, and send the result back. PDF-M works differently. When you open the page, your browser downloads a small piece of open-source code (pdf-lib). From then on, your PDFs are read and merged on your own device. Nothing is sent to us — we never see your files, so we can't store, read or lose them.

You can check this yourself: load the page, switch off Wi-Fi, and merge some files. It still works.

Why it's free

PDF-M is supported by advertising. Ads are shown around the tool, never inside it, and they never have access to your files.

Get in touch

Found a bug or have an idea? Visit the contact page.