Audio Compressor

Shrink audio files by lowering the bitrate — MP3 or OGG, in your browser, nothing uploaded.

Drop an audio file to compress it

MP3, WAV, FLAC, OGG, M4A…

Add an audio file to begin. The first run downloads the engine (~25 MB) once.

How to use

  1. Drop an audio file in, or tap the box to choose one.
  2. Pick a target bitrate — a lower number means a smaller file.
  3. Press Compress & download to save the smaller version.

FAQ

Is my audio uploaded anywhere?

No. Compression runs entirely in your browser using ffmpeg compiled to WebAssembly. Your file never leaves your device. The engine (about 25 MB) downloads once on first use and is then cached.

How does lowering the bitrate shrink the file?

Bitrate is how much data is used per second of audio. Re-encoding at a lower bitrate stores less detail, which makes the file smaller — handy for email, messaging or the web. Lower bitrates trade away some quality.

Which bitrate should I choose?

128 kbps is a good all-round MP3 for music; 96 kbps is fine for spoken word; 64 kbps is the smallest and best for voice memos where size matters most.