Black Hole Temperature Calculator

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Hawking temperature
6.168 x 10^-9 KK

The temperature at which the black hole radiates as a blackbody via Hawking radiation.

Mass1.989 x 10^31 kgkg
Mass (solar masses)10.00 M☉
Schwarzschild radius2.954 x 10^4 mm
Bekenstein-Hawking entropy1.449 x 10^56 J/KJ/K
Hawking luminosity9.003 x 10^-31 WW
Evaporation time2.10 x 10^70 years
Peak photon wavelength4.698 x 10^5 mm

Hawking temperature: 6.168 x 10^-9 K

  • The Hawking temperature is about 6.2 x 10^-9 K, far colder than the cosmic microwave background (2.725 K).
  • At 10.0 solar masses, this is a stellar-mass black hole. Its temperature is so low that it absorbs far more energy from the CMB than it radiates, so it will grow rather than evaporate under current cosmic conditions.
  • The evaporation time is 2.10 x 10^70 years, assuming no mass accretion. The current age of the universe is about 1.38 x 10^10 years.
  • The Hawking luminosity is 9.00 x 10^-31 W. For stellar-mass black holes this is negligibly small compared with conventional astrophysical processes.

Next stepHawking radiation has not yet been directly detected because stellar-mass black hole temperatures are billions of times colder than the cosmic microwave background. Primordial black holes with mass below about 5 x 10^14 kg would be evaporating today and might be observable as gamma-ray sources.

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