Wavelength & Frequency Calculator
Instantly convert between wavelength, frequency, and wave energy for any electromagnetic wave. Perfect for physics, engineering, and telecommunications.
Calculate Wave Properties
Enter either the frequency or the wavelength of an electromagnetic wave to instantly calculate its complementary property, wave energy, and period.
Wave Property Estimator
Calculate wavelength, frequency, energy, and period based on your input.
Wave Physics Formulas
Core equations used in this calculator
Wave Equation
v = f × λ
Velocity equals frequency multiplied by wavelength. In a vacuum, v is the speed of light (c ≈ 3×10⁸ m/s).
Planck-Einstein Relation
E = h × f
Photon energy equals Planck’s constant (6.626×10⁻³⁴ J·s) multiplied by frequency.
Wave Period
T = 1 / f
The period is the reciprocal of frequency, representing the time for one complete wave cycle.
Refractive Index
v = c / n
Wave velocity in a medium is the speed of light in a vacuum divided by the medium’s refractive index (n).
Electromagnetic Spectrum
A general overview of the electromagnetic spectrum, showing typical wavelength and frequency ranges for different types of electromagnetic radiation in a vacuum.
| Radiation Type | Wavelength Range | Frequency Range | Common Applications |
|---|---|---|---|
| Radio Waves | 1 m – 100,000 km | 3 Hz – 300 MHz | Radio, TV, RFID, MRI |
| Microwaves | 1 mm – 1 m | 300 MHz – 300 GHz | Wi-Fi, Radar, Microwave ovens |
| Infrared (IR) | 700 nm – 1 mm | 300 GHz – 430 THz | Thermal imaging, remote controls |
| Visible Light | 400 nm – 700 nm | 430 THz – 750 THz | Human vision, fibre optics |
| Ultraviolet (UV) | 10 nm – 400 nm | 750 THz – 30 PHz | Sterilisation, black lights, sunburn |
| X-Rays | 0.01 nm – 10 nm | 30 PHz – 30 EHz | Medical imaging, security scanning |
| Gamma Rays | < 0.01 nm | > 30 EHz | Cancer treatment, nuclear decay |
Wave Physics FAQ
Answers to the most frequently asked questions about wavelength, frequency, and electromagnetic wave calculations.
Wavelength and frequency are inversely proportional. As the frequency of a wave increases, its wavelength decreases, and vice versa. This relationship is defined by the equation v = f × λ, where v is the wave velocity, f is frequency, and λ is wavelength.
When a wave passes from one medium to another, its frequency remains constant, but its velocity changes. Because velocity changes and frequency stays the same, the wavelength must also change proportionally to the new velocity (v = f × λ).
The energy of a photon is calculated using the Planck-Einstein relation: E = h × f, where E is energy in Joules, h is Planck’s constant (6.626 × 10⁻³⁴ J·s), and f is the frequency in Hertz. Energy can also be expressed in electronvolts (eV), where 1 eV ≈ 1.602 × 10⁻¹⁹ J.
The speed of light in a vacuum (denoted as ‘c’) is exactly 299,792,458 metres per second. This is the maximum speed at which all electromagnetic radiation, including visible light, can travel.
To convert frequency (in Hertz) to wavelength (in metres), divide the speed of light (299,792,458 m/s) by the frequency. For example, a 100 MHz radio wave has a wavelength of 299,792,458 / 100,000,000 = ~2.998 metres.