Convert Grain to Gram (gr → g)
The grain is the smallest traditional weight unit, used in pharmaceutical compounding, ammunition, and arrow tips.
Grain to Gram Conversion Table
10 common values| Grain | Gram |
|---|---|
| 1 gr | 0.064799 g |
| 5 gr | 0.323995 g |
| 10 gr | 0.647989 g |
| 25 gr | 1.619973 g |
| 50 gr | 3.239946 g |
| 100 gr | 6.479891 g |
| 250 gr | 16.199728 g |
| 500 gr | 32.399455 g |
| 1,000 gr | 64.79891 g |
| 5,000 gr | 323.99455 g |
How to Convert Grain to Gram Manually
Step by StepConverting grains to grams is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.
- 1Take your value in grainsStart with the number of grains (gr) you want to convert.
- 2Multiply by 0.064799The conversion factor from gr to g is 0.064799. Multiply your value by this number.
- 3Read the result in gramsThe result is your value in grams (g).
Formula
Multiply the value in grains by 0.064799. For the reverse direction, multiply by 15.432358.
g = gr × 0.064799gr = g × 15.432358Tips
Use these in everyday conversions- 1 grain = 64.79891 mg exactly. 7000 grains = 1 pound.
- Ballistics is one of the few modern contexts where grains are essential.
- Some older pharmacology dosing survives in grain units — 5 gr ≈ 325 mg.
Common Mistakes
Avoid these- Confusing the grain (mass) with the troy grain in older precious-metal contexts — they are identical (64.8 mg).
- Assuming "grain" refers to an amount of cereal — in firearms it is always a weight.
- Reading "5 gr" as 5 grams — it is 5 grains (324 mg).
About Grain and Gram
What is the Grain?
The grain equals exactly 64.79891 milligrams (0.06479891 g) and is the smallest unit in the traditional avoirdupois weight system. Originally based on the average mass of a single grain of wheat or barley, the unit was standardized to its current value with the 1959 international yard and pound agreement. The grain is still used in pharmaceutical compounding (some older drug formulations specify grains, especially aspirin and codeine), arrow tips and ammunition (bullet weights are commonly given in grains — a 9 mm bullet is around 115 grains), and precious-metal weighing (one troy ounce = 480 grains). It relates to the ounce (437.5 grains = 1 oz avoirdupois), the pound (7,000 grains = 1 lb), and the milligram (1 grain ≈ 64.8 mg). The unit reflects medieval agriculture's role in shaping early measurement systems.
- Bullet and gunpowder mass in ballistics
- Older pharmaceutical dosing in Anglo-Saxon countries
- Arrow shaft and archery equipment weights
A 9 mm bullet typically weighs 115–124 grains (7.45–8.03 g). Aspirin grain dosing: "5 grain aspirin" = 325 mg.
What is the Gram?
The gram equals one thousandth of a kilogram (0.001 kg) and is the everyday metric unit for cooking ingredients, postage, jewelry, pharmaceuticals, and small product weights. Originally defined in 1795 as 'the absolute weight of a volume of pure water equal to a cube of one hundredth of a meter at the temperature of melting ice,' the gram is now formally defined via the kilogram. It relates simply to the milligram (1,000 mg = 1 g) and the kilogram (1,000 g = 1 kg). European nutrition labels universally use grams for ingredient quantities, and recipes worldwide outside North America measure ingredients by mass in grams rather than by volume. Gold and silver are traded in grams for small quantities, while gemstones use carats (0.2 g = 1 carat). A standard paper clip weighs about 1 g.
- European cooking and baking recipes
- Over-the-counter medication dosages
- Gold, silver and gemstone retail (per gram pricing)
A chicken egg weighs about 60 g. A standard bar of chocolate is 100 g. A euro coin weighs 7.5 g.