Compress Audio makes a sound file smaller by re-encoding it as an MP3 at the bitrate you pick: 192, 128, 96 or 64 kbps. That number decides the size — at 96 kbps a minute of audio takes about 0.7 MB, at 64 kbps about 0.5 MB — which is what you need when a voice message, lecture recording or podcast is too big for email or an upload form.
The work happens in your browser with ffmpeg; the file is not uploaded. One honest limit: compression only shrinks files that are bigger than the target. A WAV recording drops to a fraction of its size, but an MP3 that is already 64 kbps will not get smaller at 96 kbps — it can even grow.
How to use
Choose the audio file you want to shrink — WAV, M4A, FLAC, MP3 and other common formats work.
Pick a bitrate: 64 kbps for speech, 96 kbps as a balanced default, 128–192 kbps for music you still want to enjoy.
Run it, listen to the result in the page, and download the smaller MP3.
FAQ
Which bitrate should I choose?
For voice recordings, 64 kbps sounds clear and keeps files very small. For music, 128 kbps is where most people stop hearing a difference, and 192 kbps is the safe choice if the track matters. 96 kbps is the default and a reasonable middle.
Why didn't my file get smaller?
It was probably already an MP3 at or below the bitrate you chose. Re-encoding at a higher bitrate cannot make it smaller and adds a second round of lossy compression. Pick a lower bitrate, or keep the original.
What format is the result?
Always MP3, because it plays everywhere — phones, browsers, car stereos, messengers. If you need WAV or FLAC instead, use Convert Audio.
Is my file uploaded?
No. The re-encoding runs locally in your browser tab, so private recordings never leave your device. It is free and needs no account.