Convert Gram to Grain

FromGram (g)

ToGrain (gr)

Gram

The gram (g) is a unit of mass in the metric system, and it is equal to one-thousandth of a kilogram (0.001 kg). Since the kilogram is the SI base unit of mass defined by the Planck constant (h), the gram is indirectly defined by the same constant. This modern definition ensures the gram's precision and stability as part of the International System of Units (SI).

Origin:

The gram was introduced in 1795 during the French Revolution as part of the metric system's creation. Originally, it was defined as the mass of one cubic centimeter of pure water at its maximum density (approximately 4°C). This practical link to water made it a convenient and universal reference. The gram served as a base unit of mass in early metric systems, but in 1889, the kilogram was adopted as the primary standard, making the gram a derived unit equal to one-thousandth of a kilogram.

Grain

The grain (gr) is a unit of mass used in both the imperial system and the U.S. customary system. It is defined as 1/7000 of a pound or approximately 64.79891 milligrams. The grain is one of the smallest units of mass commonly used and is primarily employed in measuring the weight of precious metals, gemstones, and ammunition (such as bullets).

Origin:

The grain traces its origins to ancient times and was originally based on the weight of a single grain of cereal, such as barley or wheat, which was used as a reference for small weight measurements. The term "grain" comes from the Latin "granum", meaning "grain" or "seed." The grain was used as a standard measure in ancient civilizations, including the Romans, and its use continued throughout medieval Europe. Over time, it was standardized in the 14th century as part of the Avoirdupois system and has remained in use for very precise measurements in modern times, especially in scientific fields, medicine, and the firearm industry.