What is the wave speed formula?

Wave speed equals frequency multiplied by wavelength: v = f × λ. Rearranging gives f = v / λ (to find frequency) and λ = v / f (to find wavelength). This universal wave equation applies to sound, light, water waves, and all other wave types.

What is the speed of light?

The speed of light in a vacuum is approximately 299,792,458 m/s (roughly 3 × 10⁸ m/s). Electromagnetic waves — including radio, microwave, infrared, visible light, UV, X-rays, and gamma rays — all travel at this speed in a vacuum.

What is the speed of sound?

The speed of sound in dry air at 20°C is approximately 343 m/s. It varies with the medium and temperature: faster in liquids and solids, and increases in air as temperature rises.

What units can I use for frequency?

This calculator supports Hz, kHz, MHz, GHz, and THz. Enter the frequency in any unit and select it from the dropdown — the calculator converts automatically to SI (Hz) before computing.

What units can I use for wavelength?

Supported wavelength units include meters (m), kilometers (km), centimeters (cm), millimeters (mm), micrometers (μm), and nanometers (nm). Nanometers are commonly used for visible light (400–700 nm).

Does this work for electromagnetic waves?

Yes. For electromagnetic waves in a vacuum, enter wave speed as 299,792,458 m/s and provide either frequency or wavelength to calculate the other quantity.

Wave Speed Calculator

Name: Wave Speed Calculator
Availability: InStock
Author: Nham Vu

Solve for wave speed, frequency, or wavelength using v = f × λ with multi-unit support.

Wave Speed Calculator

Solve for

Frequency (f)

Wavelength (λ)

Enter values on the left to compute the result.

v = f × λ — Wave Equation

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Summary

Solve for wave speed, frequency, or wavelength using v = f × λ with multi-unit support.

How it works

Choose the quantity you want to solve for: Wave Speed, Frequency, or Wavelength.
Enter the two known values into the input fields.
Select the appropriate units for each value from the dropdown menus.
Click Calculate to see the result with cross-unit conversions and a worked example.
Click Clear to reset the inputs for a new calculation.

Use cases

Calculate the speed of a sound wave given its frequency and wavelength.
Find the wavelength of a radio or microwave signal from its frequency.
Determine the frequency of light given its wavelength in nanometers.
Verify wave properties in physics homework and lab reports.
Convert between frequency and wavelength for electromagnetic spectrum analysis.
Compute the wave speed of seismic or ocean waves for geophysics problems.
Explore wave behavior across the entire EM spectrum from radio to gamma rays.
Check signal wavelengths for antenna design and RF engineering calculations.

Frequently Asked Questions

Last updated: 2026-06-13 · Reviewed by Nham Vu