Calculadora de Frequência de Onda
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
f = v/λ
About this calculator
The Wave Frequency Calculator determines the frequency of a wave from its speed and wavelength. Frequency represents how many complete oscillations the wave performs per second, measured in hertz (Hz). The calculation is based on the formula f = v/λ, where v is the wave speed (in m/s) and λ is the wavelength (in meters). This fundamental relationship in wave physics applies to mechanical waves, such as sound, and electromagnetic waves, such as light.
To use the calculator, enter two known values: speed and wavelength. The tool automatically calculates the frequency. For example, for a sound wave with speed 340 m/s and wavelength 0.5 m, the frequency will be 680 Hz. If needed, you can convert units of speed (m/s, km/h) and length (m, cm, mm) via dropdown menus. The result is displayed in Hz, kHz, MHz, or GHz, depending on magnitude.
This calculator is useful in everyday, academic, and professional contexts. Physics students can verify wave exercises. Musicians and audio engineers can calculate the frequency of musical notes from the wavelength of sound in air. In telecommunications, engineers determine the frequency of radio or microwave signals. It is also applied in optics labs to characterize light sources.
Cautions: the formula assumes the wave propagates in a homogeneous and isotropic medium. Wave speed depends on the medium (e.g., sound in air at 20°C is ~343 m/s, but varies with temperature). For electromagnetic waves in vacuum, use c = 299,792,458 m/s. Ensure consistent units (meters and meters per second). The calculator does not account for effects like dispersion or attenuation.
Frequently asked questions
What if I only have frequency and wavelength?
Use the rearranged formula v = f × λ to calculate speed. Enter the known values in the calculator, leaving the speed field empty, and it will return the speed.
Does the calculator work for light waves?
Yes, as long as you use the speed of light in the appropriate medium. In vacuum, use c = 299,792,458 m/s. In other media, the speed is lower and depends on the refractive index.
How do I convert the result to kHz or MHz?
The calculator automatically displays the result in suitable units. You can also use factors: 1 kHz = 1000 Hz, 1 MHz = 1,000,000 Hz.
What is the difference between frequency and period?
Frequency (f) is the number of cycles per second. Period (T) is the time for one complete cycle: T = 1/f. The calculator gives frequency; the period can be obtained by inverting the value.
Can I use the calculator for mechanical waves in solids?
Yes, as long as you know the wave speed in the solid. The formula is universal. For example, seismic waves have typical speeds in rocks.