Semitone Calculator

Calculate the distance between two frequencies in semitones and cents

Calculate Semitone Intervals

First frequency for comparison

Second frequency for comparison

Quick Presets

Interval Results

0.000 st
Semitones Between Frequencies
0.0 ¢
Cents Between Frequencies

Frequency Ratio

0.000000

f₂ / f₁

Interval Direction

Same

Equal frequencies

Formula used: n = 12 × log₂(f₂ / f₁) for semitones; cents = 1200 × log₂(f₂ / f₁)

Input frequencies: f₁ = 0 Hz, f₂ = 0 Hz

Interval Analysis

Example Calculation

A4 Tuning Comparison

Standard A4: 440 Hz

Alternative A4: 432 Hz

Difference: Popular tuning debate

Calculation

n = 12 × log₂(432 / 440)

n = 12 × log₂(0.9818)

n = -0.318 semitones

cents = -31.8 cents

Common Musical Intervals

Unison0 st
Minor 2nd1 st
Major 2nd2 st
Minor 3rd3 st
Major 3rd4 st
Perfect 4th5 st
Tritone6 st
Perfect 5th7 st
Octave12 st

Semitone Tips

One semitone = 100 cents exactly

One octave = 12 semitones = 1200 cents

Frequency ratio of 2:1 = perfect octave

Equal temperament: 12√2 ≈ 1.0595 per semitone

Understanding Semitones and Cents

What is a Semitone?

A semitone (also called a half-step or half-tone) is the smallest musical interval commonly used in Western music. It represents the distance between two consecutive notes, such as from C to C# or from E to F on a piano keyboard.

What is a Cent?

  • A cent is 1/100 of a semitone
  • There are 1200 cents in an octave
  • Allows precise measurement of pitch differences
  • Independent of octave for same intervals

Conversion Formulas

Frequency to Semitones

n = 12 × log₂(f₂ / f₁)

Frequency to Cents

cents = 1200 × log₂(f₂ / f₁)

Semitones to Cents

cents = semitones × 100

Note: f₁ and f₂ are frequencies in Hz, n is the number of semitones