What is the Planck mass?
The Planck mass is m_P = 2.176434e-8 kg (uncertainty ±2.4e-13), or 1.220890e19 GeV/c^2. It is the mass scale of quantum gravity.
Open the interactive PhysRef tool →Key facts
| Value | 2.176434e-8 kg |
|---|---|
| Symbol | m_P |
| In GeV/c^2 | 1.220890e19 GeV/c^2 |
| Uncertainty | ±2.4e-13 kg |
| Source | CODATA 2018 |
Frequently asked questions
What is the value of the Planck mass?
m_P = 2.176434e-8 kg, or about 1.22e19 GeV/c^2, surprisingly large for a quantum scale.
How is the Planck mass defined?
m_P = sqrt(ħ·c/G), combining the fundamental constants.
Why is the Planck mass interesting?
It is roughly the mass at which a particle's Compton wavelength equals its Schwarzschild radius, marking quantum gravity.
Related pages
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