标准重力通常以g₀或g_n表示, 是在地球表面的水平线的由于地球重力而产生的额定加速度。他被定义为9.80665 m/s (approx. 32.174 ft/s)。 这个数值被第三次国际度量衡会议（CGPM） 确立 (1901, CR 70)。

标志g通常也指代重力, 但是g严格来说表示当地的重力加速度, 而这一加速度根据在地球位置的不同而不同 (参见 地球重力)。 标志g 不应该与 G混淆, 重力常量, 或者 g, 是重量单位（gram的简称 (没有斜体)。 标志g(英语又写做"gee")也被用作于加速的单位, 并用上面定义的数值(参见G力)。

The standard acceleration due to gravity (or standard acceleration of free fall), sometimes abbreviated as standard gravity, usually denoted by ɡ₀ or ɡ_n, is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth. It is defined by standard as 7000980665000000000♠9.80665 m/s, which is exactly 7000980665000000000♠35.30394 km/(h·s) (about 7000980663520000000♠32.174 ft/s, or 7000980671648000000♠21.937 mph/s). This value was established by the 3rd CGPM (1901, CR 70) and used to define the standard weight of an object as the product of its mass and this nominal acceleration. The acceleration of a body near the surface of the Earth is due to the combined effects of gravity and centrifugal acceleration from rotation of the Earth (but which is small enough to be neglected for most purposes); the total (the apparent gravity) is about 0.5 percent greater at the poles than at the equator.