Wave Speed Calculator

What Is a Wave Speed Calculator?

The Wave Speed Calculator finds the speed, frequency, or wavelength of a wave when the other two values are known. Sound, light, water ripples, and radio signals all follow the same relationship between how often a wave repeats and how far apart its peaks sit. Enter any two quantities to solve for the third.

How the Calculation Works

The three quantities are linked by one equation, and the calculator rearranges it depending on what you solve for:

$$v = f \lambda$$

$$f = \frac{v}{\lambda}, \qquad \lambda = \frac{v}{f}$$

Where:

• v is wave speed in meters per second (m/s)
• f is frequency in hertz (Hz), or cycles per second
• λ is wavelength in meters (m), the distance between matching points on the wave

Worked Example

A sound wave in air at 20 °C travels at about 343 m/s with a frequency of 1,500 Hz. Its wavelength is:

$$\lambda = \frac{343}{1500} \approx 0.229 \text{ m}$$

Going the other way, entering 1,500 Hz and a wavelength of 0.221 m returns a speed of about 331.5 m/s, which is close to the speed of sound in air near 0 °C.

Related free tools

The Wavenumber Calculator works with the spatial frequency of a wave, and the True Airspeed Calculator applies speed to flight.