About FreeBookConvert

The privacy problem with most converters

Almost every popular online file converter works by uploading your file to a server, processing it there, and sending the result back. That's fine for cat memes — but problematic for personal ebooks, private documents, business contracts, or photos you'd rather not hand to a stranger's server.

The FBI and Malwarebytes have repeatedly warned about malicious file converter sites that serve malware along with — or instead of — the converted file.

How FreeBookConvert is different

Every conversion on this site runs inside your web browser using JavaScript and WebAssembly. The libraries that do the heavy lifting (JSZip for archives, pdf-lib for PDF assembly, pdf.js for PDF parsing, libheif via heic-to for HEIC decoding) are mature open-source projects that have been used in millions of apps.

When you drop a file onto a converter page, here's what happens:

1. The file is read into your browser's memory as a Blob.
2. JavaScript code already running on the page parses it.
3. A new file is assembled in memory.
4. Your browser saves the new file to your downloads folder.

No upload. No server. You can disconnect from the internet after the page loads and everything still works.

How it stays free

FreeBookConvert is funded by unobtrusive display ads. Since there are no per-conversion server costs, ads alone are enough to keep the lights on without paywalls, signup forms, or watermarks.