What is the gravitational constant G?
The Newtonian constant of gravitation is G = 6.67430e-11 m^3·kg^-1·s^-2, with a standard uncertainty of 1.5e-15 (it is measured, not exact).
Open the interactive PhysRef tool →Key facts
| Value | 6.67430e-11 m^3 kg^-1 s^-2 |
|---|---|
| Symbol | G |
| Uncertainty | ±1.5e-15 (measured) |
| Used in | Newton's law of gravitation |
| Source | CODATA 2018 |
Frequently asked questions
What is the value of the gravitational constant?
G = 6.67430e-11 m^3·kg^-1·s^-2, one of the least precisely known fundamental constants.
Is G exact?
No. G is measured experimentally and carries a relative uncertainty around 2.2e-5 (±1.5e-15).
Where is G used?
In Newton's law F = G·m1·m2/r^2 and in Einstein's field equations of general relativity.
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