Wavelength Calculator
Calculate wavelength, frequency, energy, and wavenumber for electromagnetic waves, sound waves, and quantum particles. Enter any two known values to compute the remaining wave properties.
What Is Wavelength?
Wavelength (λ) is the distance between successive crests (or troughs) of a wave. It is a fundamental property of waves, including electromagnetic radiation, sound waves, and quantum matter waves. Wavelength is inversely proportional to frequency — waves with higher frequencies have shorter wavelengths.
The calculator supports three wave types:
- Electromagnetic Waves: Light, radio, X-rays, etc. Speed = c = 3×10⁸ m/s.
- Sound Waves: Mechanical waves in air, water, or solids.
- Quantum Waves: de Broglie wavelength of particles, λ = h / (m × v).
How Does the Wavelength Calculator Work?
The calculator uses the wave equation and quantum formulas:
Wave Equation: v = f × λ
Photon Energy: E = h × f = h × c / λ
de Broglie Wavelength: λ = h / (m × v)
Wavenumber: k = 2π / λ
Select the wave type, choose what to calculate, and enter two known values. The calculator will compute the remaining wave properties.
Why Use This Wavelength Calculator?
- Three Wave Types: Supports electromagnetic, sound, and quantum waves.
- Four Calculation Modes: Solve for wavelength, frequency, energy, or wavenumber.
- EM Spectrum Visualization: See where your wave falls on the spectrum.
- Sound Mediums: Choose from air, water, steel, glass, or custom speed.
- Free & Private: No registration, no data storage.
❓ Wavelength Calculator FAQ
What is wavelength?
Wavelength (λ) is the distance between successive peaks of a wave. It is measured in meters (m) and is inversely related to frequency.
What is the wave equation?
The wave equation is v = f × λ, where v is wave speed, f is frequency, and λ is wavelength.
How do I calculate wavelength from frequency?
Use the formula λ = v / f. For electromagnetic waves, v = c = 3×10⁸ m/s.
How do I calculate frequency from wavelength?
Use the formula f = v / λ. For electromagnetic waves, f = c / λ.
What is the speed of light?
The speed of light in vacuum is exactly 299,792,458 m/s, approximately 3×10⁸ m/s.
What is the speed of sound in air?
The speed of sound in air at 20°C is approximately 343 m/s. It varies with temperature and humidity.
What is the de Broglie wavelength?
The de Broglie wavelength is the wavelength associated with a moving particle, given by λ = h / (m × v), where h is Planck's constant.
What is Planck's constant?
Planck's constant is h = 6.62607015 × 10⁻³⁴ J·s. It relates the energy of a photon to its frequency.
How do I calculate photon energy from wavelength?
Use the formula E = h × c / λ. For example, a 500 nm photon has energy E = (6.626×10⁻³⁴ × 3×10⁸) / (500×10⁻⁹) = 3.98×10⁻¹⁹ J.
What is the electromagnetic spectrum?
The electromagnetic spectrum is the range of all types of electromagnetic radiation, from gamma rays (short wavelength) to radio waves (long wavelength).
What is the visible light spectrum?
Visible light ranges from about 400 nm (violet) to 700 nm (red).
What is wavenumber?
Wavenumber (k) is the spatial frequency of a wave, defined as k = 2π / λ. It is measured in rad/m.
What is the difference between wavelength and wavenumber?
Wavelength is the distance between wave peaks. Wavenumber is the number of wave cycles per unit distance. They are inversely related: k = 2π / λ.
How does the medium affect wavelength?
The speed of a wave depends on the medium. For a given frequency, wavelength changes with speed: λ = v / f. Sound travels faster in water and solids than in air.
What is the wavelength of a 1 GHz radio wave?
A 1 GHz radio wave has wavelength λ = c / f = 3×10⁸ / 1×10⁹ = 0.3 m (30 cm).
What is the wavelength of a 500 Hz sound wave?
A 500 Hz sound wave in air has wavelength λ = 343 / 500 = 0.686 m (68.6 cm).
How do I use this calculator for quantum mechanics?
Select "Quantum" mode, enter the particle mass and velocity (or momentum), and the calculator will compute the de Broglie wavelength.