Compress audio
Audio Compressor converts audio files to another format and bitrate. A lower bitrate gives a smaller file. Like video, it needs FFmpeg on Linux or Windows and is not available on Android.
Convert or compress audio
On the home screen, select Audio Compressor.
Add audio files: click the drop box or drag files onto it. It accepts MP3, AAC, OGG, FLAC, WAV and M4A.
Choose the output Format. MP3 is the default.
Choose a Bitrate (64 to 320 kbps; 128 kbps is the default), or a Target size.
Select Convert, for example Convert 5 files.
New files get _compressed added to their name and the new extension, for example talk_compressed.mp3.
Options
| Option | Choices |
|---|---|
| Format | MP3, AAC, OGG, FLAC, WAV, M4A |
| Bitrate | 64, 96, 128, 192, 256, 320 kbps |
| Target size | None, 5 MB, 10 MB, 25 MB |
Bitrate is how much data each second of sound uses. 128 kbps is fine for speech and most music on phones; 192 kbps or more suits music on good speakers.
With a Target size, CompressX reads the file's length and picks the bitrate that fits, between 8 and 512 kbps.
FLAC and WAV are lossless formats, so Bitrate and Target size are greyed out for them. Converting to FLAC or WAV usually makes a file bigger, not smaller.
Good to know
Converting from one lossy format to another (for example AAC to MP3) loses a little quality each time. Keep your original files if you may need them later.