MP3 Compressor.
Shrink MP3 and other audio files to a smaller size without a noticeable quality loss. Fast, easy and 100% private.
Open an audio file
Choose a file from your device to get started
Private & Secure
Compression happens locally — your original file is never uploaded.
See the Savings Live
Preview the estimated file size before you export, at any quality level.
Any Format
Compress MP3 and other audio files on any device with a browser.
Free to Use
Compress as many files as you like, with no size limit.
Tip: Lower bitrates shrink the file more but reduce quality — 128 kbps is a good balance for most audio.
How to Use & FAQ
How to Compress an MP3 File Online
- Click "Click to browse or drag & drop" and choose the audio file you want to shrink.
- Pick a quality (bitrate) and channel setting — the estimated file size updates as you choose.
- Compare the estimated size against the original to see how much you'll save.
- Click Compress & Download to export your smaller file — nothing is ever uploaded.
Frequently Asked Questions
Will compressing reduce the sound quality?
Some quality loss is expected with any lossy compression, but at 128 kbps or higher it's rarely noticeable for most listening.
What bitrate should I choose?
128 kbps is a good balance of size and quality for most audio — go higher (192-320 kbps) if quality matters more, or lower if size matters more.
Is my file uploaded to be compressed?
No — compression happens entirely in your browser using the Web Audio API and a local MP3 encoder.
What's the difference between Compressor and Converter?
Compressor is focused specifically on shrinking file size at a chosen bitrate; Converter is for changing between audio formats.
Is there a limit on file size?
No hard limit — since everything runs in your own browser, the practical limit is your device's memory.