Compress audio files
Make WAV, MP3, M4A, FLAC and other audio files smaller in your browser. Compare the original and compressed sound with an A/B switch before you download.
- Free
- No upload
- No sign-up
Your files
Compression
Looks the same, a lot smaller. Recommended.
More options
Compressed in your browser. Your files are never uploaded. Open-source libraries: mp4box.js, mp4-muxer, webm-muxer, gifenc, pdf-lib, lamejs (LGPL).
How to compress audio files
- Choose or drop audio files: WAV, MP3, M4A, AAC, FLAC or OGG.
- Pick a goal or a target size.
- Press Compress, then switch between Original and Compressed while it plays.
- Download the smaller MP3 or M4A file.
Why use Zebra Compress
Huge savings for WAV
Uncompressed WAV and FLAC recordings become 85–95 % smaller as AAC (M4A) or MP3.
Sensible bitrates
Balanced uses 112–128 kbps, which sounds the same to most listeners; MP3s already at a low bitrate are left alone.
Target size
Set a size limit and the bitrate is calculated from the length of the recording.
A/B listening
Switch between the original and the compressed sound at the same position.
Frequently asked questions
How do I make an MP3 smaller?
Choose Balanced (128 kbps) or Smallest. MP3s that are already at or below that bitrate are kept, because re-encoding them would only lose quality.
Which format is used?
MP3 files stay MP3. Other formats become M4A (AAC) when your browser can encode it, otherwise MP3.
Is mono used?
Only for very low bitrates (48 kbps or less), where mono sounds clearly better than stereo.
Are my files uploaded?
No. Everything happens in your browser on your own device. Your videos, photos and documents never leave it, so it also works with private files.
Is Zebra Compress free?
Yes. It is completely free, with no sign-up, no watermark and no limit on how many files you compress.