What This Is.

a free, in-browser tool that converts an audio file from one format to another. drop in mp3, m4a, wav, ogg, opus, flac, webm, or any video file with an audio track — pick an output format and get the converted file back.

Supported Formats.

mp3 — universal, lossy. plays everywhere.
wav — uncompressed pcm. archive-quality, large files, the format audio editors prefer as input.
m4a (aac) — apple's default. what voice memos and quicktime recordings come out as.
ogg (vorbis) — open lossy format. comparable size to mp3, slightly better quality at the same bitrate.
opus — modern lossy codec. smallest files for a given quality. ideal for speech and modern playback chains.
flac — lossless compression. smaller than wav, identical audio. archive format.

Nothing Uploads.

most "convert audio" tools are server-side services. you upload your file, their server processes it, you download the result. for most files that's fine — but for sensitive material (interviews under embargo, client-confidential audio, off-the-record recordings, audio you'd rather not have copies of on a third-party server), it isn't.

this tool runs ffmpeg.wasm directly in your browser. the file you drop is read into the browser's memory, decoded locally, and re-encoded locally. no network request happens at any point during the conversion. you can verify this in your browser's network tab — and we wrote a five-minute walkthrough on doing exactly that audit.

How To Use It.

drop your audio (or video) file into the target above (or click to choose).
pick the output format from the dropdown.
hit convert. the result downloads to your machine; nothing reaches us.

Which Format Should I Pick.

mp3 for sharing or web embed. plays in every browser, every app, every device.
wav when feeding an audio editor. lossless, no codec surprises.
flac for archive. lossless and roughly half the size of wav.
m4a when your editor or pipeline demands it.
opus if you're modern and care about file size. smallest at equivalent quality.