Black hole evaporation time
Black hole evaporation time also called as black hole lifetime or Hawking evaporation timescale. It refers to the duration required for a black hole to completely lose all its mass through Hawking radiation and disappear.
This process is extremely slow for any realistic black hole. It is far longer than the current age of the universe (~13.8 billion years ≈ 10¹⁰ years, proximate). Only tiny black holes (hypothetical primordial ones) could evaporate on shorter timescales.
Evaporation Times Comparison
| Black Hole Type |
Mass (Solar masses) |
Approx. Lifetime |
Compared to Universe Age (~13.8 billion years) |
| Tiny primordial (evaporating now) |
~10⁻¹⁸ M☉ |
~10¹⁰ years |
≈ current age |
| Small primordial |
~10⁻²⁰ – 10⁻¹⁵ M☉ |
Already evaporated |
— |
| Typical stellar-mass |
1 – 100 M☉ |
10⁶⁷ – 10⁷¹ years |
10⁵⁷ – 10⁶¹ × longer |
| Supermassive (Sgr A*) |
~4 × 10⁶ M☉ |
~10⁸⁵ – 10⁸⁶ years |
~10⁷⁵ × longer |
| Ultra-massive |
10¹⁰ – 10¹¹ M☉ |
10⁹³ – 10⁹⁶ years |
Truly cosmic timescales |
Today: 13.8 billion years
| 10⁶⁷ years | → most stellar black holes evaporate |
| 10⁸⁵–10⁸⁶ years | → supermassive black holes begin to vanish |
| 10⁹⁴+ years | → even the largest black holes disappear |
