Harmonic Series Calculator

Calculate harmonic frequencies and explore the mathematical foundation of musical harmony

Calculate Harmonic Series

Root note of the harmonic series

Octave number (4 = middle octave)

How many harmonics to calculate

Fundamental Frequency

C4
Note
261.63 Hz
Frequency

Harmonic Series Results

HarmonicFrequency (Hz)NoteIntervalRatioCents
1261.63D#4Unison1:10
2523.25D#5Unison + 1 octave2:10
3784.88A#5Perfect 5th + 1 octave3:1+2
41046.50D#6Unison + 2 octaves4:10
51308.13G6Major 3rd + 2 octaves5:1-14
61569.75A#6Perfect 5th + 2 octaves6:1+2
71831.38C#6Minor 7th + 2 octaves7:1-31
82093.00D#7Unison + 3 octaves8:10
92354.63F7Major 2nd + 3 octaves9:1+4
102616.26G7Major 3rd + 3 octaves10:1-14
112877.88A7Tritone + 3 octaves11:1-49
123139.51A#7Perfect 5th + 3 octaves12:1+2
133401.13B7Minor 6th + 3 octaves13:1+41
143662.76C#7Minor 7th + 3 octaves14:1-31
153924.38D7Major 7th + 3 octaves15:1-12
164186.01D#8Unison + 4 octaves16:10

Cents: Deviation from equal temperament tuning (0 = perfect match)

Color coding: Green ≤5¢, Yellow ≤10¢, Orange ≤20¢, Red >20¢

Common Harmonic Intervals

Perfect Intervals

Octave (2:1)Perfect
Perfect 5th (3:2)+2 cents
Perfect 4th (4:3)-2 cents

Problematic Intervals

7th Harmonic-31 cents
11th Harmonic-49 cents
Major 3rd (5:4)-14 cents

Common Fundamentals

Music Theory Tips

Lower harmonics sound more consonant than higher ones

The 7th and 11th harmonics create notable dissonance

Simple ratios (2:1, 3:2, 4:3) sound more pleasing

Harmonic series forms the basis of just intonation

Instrument timbre depends on harmonic content

Applications

Instrument Design

Understanding resonant frequencies

Audio Synthesis

Creating realistic instrumental sounds

Tuning Systems

Comparing equal temperament vs just intonation

Acoustics

Room acoustics and speaker design

Understanding the Harmonic Series

What is the Harmonic Series?

The harmonic series is a sequence of frequencies that are integer multiples of a fundamental frequency. When you hear a musical note, you're actually hearing the fundamental frequency plus many of these harmonic overtones, which give the instrument its unique timbre.

Mathematical Foundation

  • 1st Harmonic: f (fundamental frequency)
  • 2nd Harmonic: 2f (octave)
  • 3rd Harmonic: 3f (perfect fifth above octave)
  • nth Harmonic: n × f

Just Intonation vs Equal Temperament

Just Intonation: Based on simple integer ratios from the harmonic series

Equal Temperament: Divides the octave into 12 equal semitones

Cents Deviation

Cents measure the difference between just intonation (harmonic series) and equal temperament. One semitone = 100 cents, so small deviations (±5 cents) are barely noticeable, while larger deviations (±30 cents) create noticeable dissonance.

Fun Fact: The harmonic series explains why certain intervals sound consonant (simple ratios like 2:1, 3:2) while others sound dissonant (complex ratios like 11:8).

Practical Applications

Instrument Timbre

Different instruments emphasize different harmonics, creating their unique sound character. A flute has mainly the fundamental, while a violin has rich harmonic content.

Chord Theory

Major and minor chords are built from the harmonic series. The major triad (4:5:6 ratio) appears naturally in the series, explaining its consonant sound.

Audio Engineering

Understanding harmonics is crucial for EQ, distortion effects, and synthesizer programming. Adding or removing specific harmonics shapes the sound.