Audio Compressor
What the audio compressor does
Audio files can be large — a few minutes of music or a long voice recording easily runs to tens of megabytes, which is awkward to email, upload, or store. This tool re-encodes your audio as an MP3 at a bitrate you choose, producing a much smaller file that plays anywhere.
Choosing a bitrate
Bitrate is the size-versus-quality dial. Lower bitrates (64–96 kbps) make the smallest files and are ideal for speech, podcasts, and voice notes. Higher bitrates (128–192 kbps) keep more detail for music. If you are unsure, 128 kbps is a balanced everyday default. One caveat: if your file is already a low-bitrate MP3, pick a bitrate below the original to actually make it smaller.
Private and on-device
Everything happens in your browser: the file is decoded and re-encoded to MP3 locally using a bundled encoder, so your audio is never uploaded to a server. The output is a standard MP3 that works in every player and on every device.
Frequently asked questions
Is my audio uploaded?
No. The file is decoded and re-encoded to MP3 entirely in your browser, so the audio never leaves your device.
Which formats can I compress?
Anything your browser can decode — MP3, WAV, M4A/AAC, OGG, and usually FLAC — up to 100 MB. The output is always a widely-compatible MP3.
How do I control the size?
Pick a bitrate: a lower one (like 64–96 kbps) makes the smallest files and is great for voice or podcasts, while a higher one (128–192 kbps) keeps more quality for music. Each option shows what it is best for.
Why did my file get bigger?
If your original was already a low-bitrate MP3, re-encoding at a higher bitrate can add size — choose a lower bitrate than the original to actually shrink it.