Note Frequency Calculator
Convert between musical notes and frequencies in Hz
Note Frequency Calculator
Choose the musical note
Octave number (-1 to 9)
Precision for frequency display
Reference frequency for A4 (usually 440 Hz)
Results
Note: A4 | Scientific Notation: A4 | Sound Speed: 343 m/s (20°C)
Calculation Formula
Note to Frequency: f = f₀ × 2^((n-n₀)/12)
Where: f₀ = 440 Hz (A4), n = MIDI note number, n₀ = 69 (A4)
Wavelength: λ = v/f (v = 343 m/s at 20°C)
Cents: 1200 × log₂(f₁/f₂) cents between frequencies
Common Note Frequencies
| Note | Octave 2 | Octave 3 | Octave 4 | Octave 5 | Octave 6 |
|---|---|---|---|---|---|
| C | 65.4 Hz | 130.8 Hz | 261.6 Hz | 523.3 Hz | 1046.5 Hz |
| C♯/D♭ | 69.3 Hz | 138.6 Hz | 277.2 Hz | 554.4 Hz | 1108.7 Hz |
| D | 73.4 Hz | 146.8 Hz | 293.7 Hz | 587.3 Hz | 1174.7 Hz |
| D♯/E♭ | 77.8 Hz | 155.6 Hz | 311.1 Hz | 622.3 Hz | 1244.5 Hz |
| E | 82.4 Hz | 164.8 Hz | 329.6 Hz | 659.3 Hz | 1318.5 Hz |
| F | 87.3 Hz | 174.6 Hz | 349.2 Hz | 698.5 Hz | 1396.9 Hz |
| F♯/G♭ | 92.5 Hz | 185.0 Hz | 370.0 Hz | 740.0 Hz | 1480.0 Hz |
| G | 98.0 Hz | 196.0 Hz | 392.0 Hz | 784.0 Hz | 1568.0 Hz |
| G♯/A♭ | 103.8 Hz | 207.7 Hz | 415.3 Hz | 830.6 Hz | 1661.2 Hz |
| A | 110.0 Hz | 220.0 Hz | 440.0 Hz | 880.0 Hz | 1760.0 Hz |
| A♯/B♭ | 116.5 Hz | 233.1 Hz | 466.2 Hz | 932.3 Hz | 1864.7 Hz |
| B | 123.5 Hz | 246.9 Hz | 493.9 Hz | 987.8 Hz | 1975.5 Hz |
Quick Reference
A4 (Concert Pitch)
440 Hz
Standard tuning reference
Middle C (C4)
261.63 Hz
Piano middle C
Guitar Low E (E2)
82.41 Hz
6th string, standard tuning
Music Theory Tips
Each octave doubles the frequency
12 semitones = 1 octave = 2× frequency
100 cents = 1 semitone difference
Equal temperament divides octave into 12 equal parts
Understanding Musical Frequencies
What is Frequency?
Frequency is the number of sound wave cycles per second, measured in Hertz (Hz). In music, frequency determines the pitch we hear - higher frequencies sound higher, lower frequencies sound lower. Musical notes have specific frequencies based on mathematical relationships.
Scientific Pitch Notation
Notes are named using letters A-G with optional sharps (♯) or flats (♭), followed by an octave number. For example, A4 is the A above middle C, which vibrates at 440 Hz in standard tuning.
Equal Temperament
Modern Western music uses twelve-tone equal temperament, where each semitone (half step) represents a frequency ratio of 2^(1/12) ≈ 1.059. This system allows instruments to play in any key while maintaining consistent intervals.
Practical Applications
- •Tuning musical instruments
- •Audio engineering and synthesis
- •Music education and theory
- •Sound wave analysis
Common Tuning Standards
A440 (Concert Pitch)
440 Hz
International standard since 1955. Most common tuning.
A432 (Scientific Pitch)
432 Hz
Alternative tuning claimed to be more harmonious.
A415 (Baroque Pitch)
415 Hz
Historical tuning for period instruments.