What This Calculator Does
Every object radiates light across a range of wavelengths depending on its temperature, with one wavelength carrying the most intensity — the peak. Wien’s Displacement Law predicts that peak wavelength directly from temperature, which is how astronomers estimate star temperatures from their color.
The Formula
Wien’s Law states λmax = b / T, where T is the absolute temperature in Kelvin and b is Wien’s displacement constant, approximately 2,897,771.9 nm·K. A hotter object peaks at a shorter (bluer) wavelength, while a cooler object peaks at a longer (redder or infrared) wavelength — this is why the Sun’s surface (about 5,778 K) peaks near visible yellow-green light.
Note: This calculation assumes the object behaves as an ideal blackbody radiator, which is a good approximation for stars and heated filaments but only approximate for real-world objects with reflective or non-uniform surfaces. Intended for general educational purposes.