The spectroscopy wavelength reference converts wavelengths, frequencies, and photon energies across the electromagnetic spectrum. Enter a wavelength in any unit to identify its spectrum region and compute all corresponding properties.
Wavelength / Frequency / Energy Converter
Applications
Electromagnetic Spectrum
| Region | Wavelength | Frequency | Photon Energy | Applications |
|---|---|---|---|---|
| Radio | >1 mm | <300 GHz | <1.2 meV | Radio, TV, MRI |
| Microwave | 1mm–1m | 300 MHz–300 GHz | 1.2 μeV–1.2 meV | Radar, microwave ovens |
| Infrared | 700nm–1mm | 300 GHz–430 THz | 1.2 meV–1.7 eV | Heat, night vision, remote controls |
| Visible | 380–700nm | 430–790 THz | 1.7–3.3 eV | Human vision |
| UV | 10–380nm | 790 THz–30 PHz | 3.3–124 eV | Sterilization, phototherapy |
| X-ray | 0.01–10nm | 30 PHz–30 EHz | 124 eV–124 keV | Medical imaging, crystallography |
| Gamma | <0.01nm | >30 EHz | >124 keV | Nuclear medicine, cancer therapy |
How to Use the Spectroscopy Wavelength Reference
The electromagnetic spectrum spans from radio waves (meters long) to gamma rays (smaller than an atom). This reference converts between wavelength, frequency, and photon energy, and identifies which region of the spectrum your value falls in.
Step 1: Choose Input Type
Select whether you want to enter a wavelength (nm, μm, or m), a frequency (Hz or THz), or a photon energy (eV or J). The calculator converts to all other representations.
The Key Relationships
Speed of light c = λ × f (wavelength × frequency = 3×10⁸ m/s). Photon energy E = hf = hc/λ, where h = 6.626×10⁻³⁴ J·s. In practical units: E(eV) = 1240 / λ(nm). A 500nm photon has energy = 1240/500 = 2.48 eV.
Common Spectroscopy Examples
Sodium D-line: 589 nm (yellow visible light, 2.1 eV). Hydrogen H-alpha: 656 nm (red, 1.89 eV). CO₂ laser: 10.6 μm (mid-infrared, 0.12 eV). X-ray diagnostic: 0.1 nm (12.4 keV). Green laser pointer: 532 nm (2.33 eV).
Unit Conversions
1 nm = 10⁻⁹ m. 1 μm = 10⁻⁶ m = 1000 nm. 1 THz = 10¹² Hz. 1 eV = 1.602×10⁻¹⁹ J. For frequency in THz, multiply Hz by 10⁻¹².
FAQ
What are the regions of the electromagnetic spectrum?
From longest to shortest wavelength: Radio (>1m), Microwave (1mm–1m), Infrared (700nm–1mm), Visible light (380–700nm), Ultraviolet (10–380nm), X-rays (0.01–10nm), and Gamma rays (<0.01nm). Higher frequency = shorter wavelength = more energy per photon.
What is the relationship between wavelength, frequency, and energy?
Wavelength and frequency are related by c = λf, where c = 3×10⁸ m/s. Photon energy is E = hf = hc/λ, where h = 6.626×10⁻³⁴ J·s (Planck's constant). Shorter wavelength = higher frequency = higher energy.
What are the colors of visible light?
Violet (380–450nm), Blue (450–495nm), Green (495–570nm), Yellow (570–590nm), Orange (590–620nm), Red (620–700nm). White light contains all these wavelengths; a prism or diffraction grating separates them.
Is this reference free?
Yes, completely free with no signup required. All calculations run in your browser.
How do I convert wavelength in nm to eV?
Energy in eV = 1240 / wavelength in nm. This comes from E = hc/λ with hc = 1240 eV·nm. Example: 500nm green light = 1240/500 = 2.48 eV. UV light at 250nm = 4.96 eV.