Bit Rate, sometimes also written as bitrate, indicates the amount of data that is processed or delivered over a certain time span. The data is measured in bits while the time is measured in seconds, resulting in a bit/s or bps (bits by seconds) unit. When dealing with a high Bit Rate, the unit can also be expressed in kilobit (kbps), megabit (mbps), gigabit (gbps), and so on.
When talking about the Bit Rate of audio or video files, it often affects the quality of the audio data in both cases. As a rule of thumb, the higher the Bit Rate, the better the audio quality. For example, an MP3 file with a Bit Rate of 192 kbps will have a considerably better quality than a file that has a Bit Rate of only 32 kbps. Furthermore, the Bit Rate affects the image quality of a video file.
How can this be explained? It’s easy: the higher the Bit Rate, the more data is transmitted during playback time – and vice versa. That means that more and clearer data can be delivered in a higher Bit Rate, thus resulting into an overall better quality.
The Bit Rate of a file also affects the file size of an audio or video file. Generally, files of better quality and thus a higher Bit Rate have a higher file size than files with a lower quality and thus lower Bit Rate.