What is a musical interval?

A musical interval is the distance in pitch between two notes. It is measured in semitones (half-steps on a piano) and named by its quality and number, such as "Major Third" or "Perfect Fifth."

What is the difference between just intonation and equal temperament?

Just intonation uses simple integer ratios (e.g. 3:2 for a Perfect Fifth) derived from the harmonic series, which sound very pure. Equal temperament divides the octave into 12 equal semitones so every key is in tune with every other key, at the cost of slight inaccuracies vs. just ratios. Modern pianos use equal temperament.

What are consonant vs. dissonant intervals?

Consonant intervals sound stable and pleasing (Unison, Octave, Perfect Fourth, Perfect Fifth, Major/Minor Third, Major/Minor Sixth). Dissonant intervals create tension (Minor 2nd, Major 2nd, Tritone, Minor 7th, Major 7th). The Tritone is the most dissonant interval in Western music theory.

What happens for intervals larger than an octave?

Intervals larger than 12 semitones are called compound intervals. For example, 14 semitones is a Major Ninth (an octave plus a Major Second). This calculator shows the compound name and total semitone count.

Music Interval Calculator

Name: Music Interval Calculator
Availability: InStock
Author: Nham Vu

Select any two notes (pitch + octave) and get the interval name, semitones, cents, just-intonation ratio, equal-temperament ratio, quality, and consonance rating instantly.

Select Notes

Note 1

261.63 Hz

Direction

Note 2

392.00 Hz

Select two notes and click Calculate

Default: C4 → G4

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Summary

Select any two notes (pitch + octave) and get the interval name, semitones, cents, just-intonation ratio, equal-temperament ratio, quality, and consonance rating instantly.

How it works

Select the first note (pitch and octave) from the Note 1 dropdowns.
Select the second note (pitch and octave) from the Note 2 dropdowns.
Choose the direction — Ascending (Note 1 to Note 2 upward) or Descending.
Click Calculate to see the full interval analysis on the right panel.
Click Reset to clear both notes and start over.

Use cases

Music students: quickly verify interval names and qualities while studying music theory.
Composers: check the consonance of note pairs before writing harmonies.
Teachers: demonstrate the difference between just-intonation and equal-temperament ratios.
Guitarists and pianists: find the semitone distance between any two frets or keys.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu