Music Interval Calculator
Find the frequency of a note that is a given musical interval above or below a starting pitch, using equal temperament tuning.
What this calculator does
Musical intervals describe the distance in pitch between two notes. This calculator uses 12-tone equal temperament, the tuning system used by most modern instruments like pianos and guitars, to find the frequency of a note a given number of semitones above or below a starting pitch.
The formula
In equal temperament, each semitone represents a frequency ratio of the 12th root of 2 (about 1.0595). To move up or down by n semitones, multiply the starting frequency by 2 raised to the power of n divided by 12. Moving up an octave (12 semitones) always doubles the frequency.
This tool is for general music theory and educational reference. Real-world instrument tuning can vary slightly depending on temperament and context.