Photon Energy Calculator
Calculate photon energy: E = hf = hc/lambda. Enter frequency or wavelength.
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Enter either a frequency in Hz or a wavelength in nanometers (leave the other blank). The calculator uses E = hf or E = hc/lambda to find the photon energy in joules and electronvolts.
About the Photon Energy Calculator
Photon energy is the fundamental quantum of electromagnetic radiation. Each photon carries energy proportional to its frequency (E = hf) and inversely proportional to its wavelength. Understanding photon energy is essential for spectroscopy, photochemistry, laser technology, and quantum mechanics.
Frequently Asked Questions
What is the relationship between energy and wavelength?
Energy is inversely proportional to wavelength: E = hc/lambda. Shorter wavelengths (like UV and X-rays) have higher energy. Longer wavelengths (like radio waves) have lower energy.
What are electronvolts?
An electronvolt (eV) is the energy gained by an electron moving through a 1-volt potential difference. 1 eV = 1.602 x 10^-19 J. It is convenient for atomic and molecular energies because the numbers are more manageable.
What is visible light energy?
Visible light ranges from about 400 nm (violet, 3.1 eV) to 700 nm (red, 1.8 eV). UV light has higher energy (shorter wavelength), and infrared has lower energy (longer wavelength).