Frequency Calculator Formula

Understand the math behind the frequency calculator. Each variable explained with a worked example.

Formulas Used

Frequency

frequency = wave_speed / wavelength

Period

period = wavelength / wave_speed

Variables

VariableDescriptionDefault
wave_speedWave Speed(m/s)343
wavelengthWavelength(m)0.78

How It Works

Frequency

Frequency is the number of complete wave cycles passing a point per second.

Formula

f = v / lambda

The reciprocal of frequency is the period: T = 1 / f = lambda / v.

Worked Example

Sound traveling at 343 m/s with a wavelength of 0.78 m.

wave_speed = 343wavelength = 0.78
  1. 01f = v / lambda
  2. 02f = 343 / 0.78
  3. 03f = 439.7 Hz
  4. 04T = 1 / f = 0.002274 s

Frequently Asked Questions

What is the audible frequency range for humans?

Roughly 20 Hz to 20,000 Hz. Frequencies below 20 Hz are infrasound; above 20 kHz are ultrasound.

How does frequency relate to pitch?

Higher frequency corresponds to higher perceived pitch. Doubling the frequency raises the pitch by one octave.

Can frequency change as a wave moves between media?

No. Frequency stays constant when a wave passes from one medium to another; it is the wavelength and speed that change.

Learn More

Guide

Understanding the Electromagnetic Spectrum

A complete guide to the electromagnetic spectrum. Learn about radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays, including their wavelengths, frequencies, and applications.

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