Frequency Calculator
Calculate wave frequency from wavelength and speed (f = v / λ), or from period (f = 1 / T).
Sound: ~343 m/s · Light: 299,792,458 m/s
Enter wavelength and wave speed to calculate frequency.
Frequency Formula
f = v / λ
f = 1 / T
f = 1 / T
Frequency (f) is the number of complete wave cycles per second. It's measured in hertz (Hz), where 1 Hz = 1 cycle/second.
Example: Sound with wavelength 0.68 m in air (343 m/s).
f = 343 / 0.68 = 504.4 Hz (approximately middle C)
f = 343 / 0.68 = 504.4 Hz (approximately middle C)
Common Frequencies
| Source | Frequency |
|---|---|
| Human hearing range | 20 Hz – 20 kHz |
| Middle C (music) | 261.6 Hz |
| WiFi (2.4 GHz) | 2.4 × 10⁹ Hz |
| Visible light | 430 – 790 THz |
FAQ
What is the relationship between frequency and pitch?
Higher frequency = higher pitch. Doubling the frequency raises the pitch by one octave.
What is angular frequency?
Angular frequency ω = 2πf. It measures rotational rate in radians per second.
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Last updated: 2026-08-08