BuzzKit
Audio Compressor
Lower the bitrate to shrink an audio file's size.
Lower bitrates shrink the file more but reduce fidelity — 96–128 kbps is a common sweet spot for speech and casual listening.
How the audio compressor works
This tool re-encodes your audio to MP3 at the bitrate you choose, trading some fidelity for a smaller file — the same lever any audio compressor uses.
Drop your audio file
Preview it first.
Set the bitrate
Lower for smaller files, higher for better quality.
Compress & download
Get back a smaller MP3.
Using the audio compressor well
Audio compression here means lowering the bitrate: the tool re-encodes your file to MP3 at the bitrate you pick, and a lower bitrate gives a smaller file with less detail. Speech, lectures and voice memos usually tolerate a low bitrate well, while music benefits from a higher one.
Re-encoding a lossy file always costs a little fidelity, so keep your original and work on a copy. If the recording is also longer than you need, trim it first with the Audio Trimmer, which means fewer minutes to compress. To change the format instead of the size, use the Audio Converter.
Frequently asked questions
What bitrate should I use?
96–128 kbps works well for speech and podcasts; 192–256 kbps preserves music better.
Does this always output MP3?
Yes, the compressed output is always MP3 regardless of the source format.
Can I compress without any quality loss?
No — bitrate reduction is inherently lossy; use the Audio Converter for a lossless format switch instead.
Are my audio files uploaded anywhere?
No. The compression runs in your browser tab using ffmpeg compiled to WebAssembly, so your file stays on your device.
How much smaller will my file get?
That depends on the original bitrate and the one you choose. Dropping a 320 kbps file to 128 kbps cuts its data rate by 60%, and the file size falls by about the same proportion.