What is Equal Temperament?

Equal temperament is a tuning system in which the octave is divided into equal pitch intervals, allowing instruments to play in any key with the same relative tuning. In the most common form, called twelve-tone equal temperament, the octave is divided into twelve equal semitones.

In this system, each step between notes has the same frequency ratio, meaning the distance between every adjacent pair of notes is identical. This uniform spacing allows musicians to transpose music easily and perform in multiple keys without retuning instruments.

Equal temperament is the standard tuning system used in most modern Western music, especially for instruments such as pianos, guitars, and keyboards. Although some intervals are slightly adjusted compared to natural tuning systems like just intonation, equal temperament provides the flexibility needed for complex harmonic and key changes.