About AudioKit
Practical audio tools that run entirely in your browser.
What AudioKit is
AudioKit is a small collection of audio tools: a converter for every common format (with video files welcome as sources), a trimmer, a merger, a compressor, volume and loudness normalization, a speed changer and a silence trimmer. Every tool is free, needs no account and works on any modern browser, desktop or mobile.
How it works
The tools are powered by ffmpeg, the open-source audio and video engine, compiled to WebAssembly so it runs inside your browser. The engine (about 31 MB) downloads the first time you run a job and is cached afterwards. Your files are decoded, processed and encoded on your own device; nothing is uploaded, which also means there are no size-based fees and no queues.
Why it's free
The site is supported by ads. Because the work happens on your device, there are no servers to pay for, which is what keeps every tool free without limits, watermarks or paid tiers.
The tech
ffmpeg.wasm (LAME for MP3, Vorbis, FLAC and AAC encoders) does the audio work; the pages themselves are plain static HTML. AudioKit is part of the Tool-Kits family together with PixKit, VidsKit, PdfKit, CvKit and QrKit, which share the same design and the same code.