What is a Bit Depth?

Bit depth refers to the number of bits used to represent the amplitude, or loudness level, of each audio sample in a digital recording. It determines how precisely the volume of a sound can be measured and stored. Higher bit depth allows for more possible amplitude values, which results in greater dynamic range and more accurate audio reproduction.

Common bit depths used in digital audio include 16-bit, 24-bit, and sometimes 32-bit floating point in professional recording environments. For example, 16-bit audio—commonly used for CDs—provides about 65,536 possible amplitude levels, while 24-bit audio offers millions of possible levels. This increased precision helps reduce noise and improves the ability to capture both very quiet and very loud sounds.

Bit depth works together with sample rate to determine the overall quality of digital audio. While sample rate controls how often the signal is measured over time, bit depth determines how accurately each measurement captures the signal’s loudness. Higher bit depths are especially useful during recording and mixing because they provide more headroom and greater detail in the audio signal.