How I Built a Browser-Based Video Converter With FFmpeg & WebAssembly — No Server Required

TL;DR FFmpeg compiled to WebAssembly runs entirely in the browser. No file uploads, no backend, no cost. Here's how it works and why it matters. The problem with every online video converter You need to convert a video. You Google "free online video converter," pick one of the top results, and upload your file. Then you wait. The file is 800MB. You wait more. You get an email. You download the converted file. You realize it's watermarked. You pay $9.99 to remove the watermark. We've all been here. The model is broken by design — your file goes to someone else's server, gets processed there, and you hope for the best with your privacy. I wanted to fix this. So I built videoconverter.live — a video converter that runs 100% in your browser using FFmpeg compiled to WebAssembly. Your file never leaves your device. What is FFmpeg.wasm? FFmpeg is the industry-standard open-source multimedia framework. YouTube uses it. VLC uses it. Chrome uses it. It supports virtually every codec and containe