Blackbody
Joachim Köppen Kiel May 2017

The blackbody spectrum is the thermal emission of a perfectly absorbing body at a given temperature. This tool displays the spectrum as a function of frequency, wavelength, and energy in terms of photon flux or energy flux (red curve). It also computes the energy or the number of photons emitted in a given frequency band (between blue vertical lines).

Hitting the Enter key after entering a parameter will refresh the display.


Temperature [K]:

Integration between


energy flux [W/m²]:
fraction of energy flux:
photon flux [phot/s/m²]:
fraction of photon flux:

X =
Y =


Mouse position:

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