About MP3 Compressor
An MP3's size depends almost entirely on its bitrate and length. A one-hour recording at 192 kbps is about 86 MB, while the same hour at 64 kbps is about 29 MB. Lowering the bitrate is the most effective way to make an MP3 fit an upload limit or a messaging app, and for spoken audio the drop in quality is often hard to notice. This compressor decodes each MP3 and re-encodes it at the bitrate you choose, with a mono option that halves the size of voice recordings.
How to Use It
- 01
Add MP3 files
Drop .mp3 files into the box, or tap it to choose them.
- 02
Choose a bitrate
Pick a bitrate lower than the original. 64-96 kbps mono suits speech; 128 kbps stereo suits music.
- 03
Compress
Press Compress, compare the sizes, and download the smaller MP3s.
Questions
How do I know the original bitrate?
Your music player or file properties usually show it. As a rough guide, divide the file size in kilobits by the length in seconds. Choose a lower bitrate, or the file won't shrink.
Will it sound worse?
Re-encoding at a lower bitrate removes some detail. Speech holds up well down to 64 kbps; music starts to lose clarity below about 128 kbps.
Should I choose mono?
For podcasts, lectures and voice notes, yes. Mono needs half the data for similar quality. Keep stereo for music.
Are tags like title and artist kept?
No. The compressed MP3 contains the audio only; add tags again in a music library app if you need them.