Audio Bitrate Guide: What It Means and What to Choose
Bitrate is the single most important quality setting when encoding audio. Here's what it means, how it affects quality and file size, and what to choose for each use case.
Advertisement
What Is Audio Bitrate?
Bitrate is the number of bits (units of digital data) used to encode one second of audio, measured in kilobits per second (kbps). Higher bitrate = more data per second = better audio quality = larger file size. A 320kbps MP3 uses 320,000 bits to represent each second of audio; a 128kbps MP3 uses less than half that data.
How Bitrate Affects Quality
Below about 128kbps, lossy audio quality degradation becomes audible to most listeners: compression artefacts, 'watery' or 'bubbly' sounds on complex audio, reduced high-frequency clarity. Above 256kbps with modern codecs like AAC, the vast majority of listeners cannot detect quality loss versus the original source. The relationship is logarithmic — the quality jump from 64 to 128kbps is massive; from 256 to 320kbps is negligible.
Recommended Bitrates by Use Case
| Use Case | Codec | Recommended Bitrate |
|---|---|---|
| Voice / speech | MP3 mono | 32-64 kbps |
| Podcast | MP3 mono | 64-96 kbps |
| Background music / web | AAC or MP3 | 96-128 kbps |
| Music (streaming quality) | AAC | 128-192 kbps |
| High-quality music | AAC or MP3 | 256-320 kbps |
| Lossless archiving | FLAC | N/A (lossless) |
| Professional production | WAV | N/A (uncompressed) |
Compress or convert audio
Reduce audio file size or convert format with custom bitrate settings.
Frequently Asked Questions
Does a higher bitrate always mean better quality?
Up to the quality ceiling of the source audio. If your source is a low-quality recording, encoding it at 320kbps doesn't improve the recording quality — it just stores the poor quality without additional compression loss. Always start from the highest-quality source available. Re-encoding from a low-bitrate MP3 to a higher bitrate doesn't improve quality.