Convert weight and mass units — kilograms, pounds, grams, ounces, tons, carats and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 gr | 6.48e-08 kg | |
| 0.01 gr | 6.48e-07 kg | |
| 0.1 gr | 6.48e-06 kg | |
| 1 gr | 6.48e-05 kg | |
| 5 gr | 0.000324 kg | |
| 10 gr | 0.000648 kg | |
| 50 gr | 0.00324 kg | |
| 100 gr | 0.00648 kg | |
| 1000 gr | 0.0648 kg |
The Milligram (mg) and the Gram (g) are both units of weight & mass. Converting between them is straightforward using the formula above.
Formula: 1 gr = 0.0000648 kg
This converter uses internationally recognized conversion factors. All calculations are performed client-side in your browser — no data is sent to any server.
| Grain (gr) | Kilogram (kg) | Real-world context |
|---|---|---|
| 1 gr | 6.4800e-05 kg | grain of wheat |
| 1000 gr | 0.0648 kg | |
| 1,000,000 gr | 64.8 kg | |
| 1.0000e+09 gr | 64800 kg | |
| 1.0000e+12 gr | 64,800,000 kg |
1 grain (gr) equals exactly 6.4800e-05 kilograms (kg). Use the formula: gr × 6.4800e-05 = kg.
To convert grains to kilograms, multiply your value in grains by 6.4800e-05. For example, 5 gr × 6.4800e-05 = 0.000324 kg.
100 grains = 0.00648 kilograms. Calculation: 100 × 6.4800e-05 = 0.00648.
To convert kilograms back to grains, divide by 6.4800e-05 (or multiply by 15432.0988). Example: 10 kg ÷ 6.4800e-05 = 154320.9877 gr.
Yes. This converter uses the internationally recognised exact conversion factor: 1 gr = 6.4800e-05 kg. All calculations are performed in your browser with no rounding until display.
10 grains = 0.000648 kilograms. Simply multiply by 6.4800e-05.
Converting grains to kilograms is commonly needed for jewellery valuation, gemstone trading, precious metal buying and selling, and hallmarking compliance where one system uses gr and another uses kg.
The grain (gr) is the smallest unit in the avoirdupois, troy, and apothecary weight systems, equal to exactly 64.79891 milligrams (0.06479891 g). All three systems share the same grain as base: one avoirdupois pound = 7,000 grains; one troy pound = 5,760 grains. The grain is still used in ballistics (bullet and powder weights) and some pharmaceutical contexts.
The kilogram (kg) is the SI base unit of mass — one of seven fundamental units in the International System. Equal to exactly 1,000 grams, it is the foundation of weight measurement in science, medicine, engineering, and commerce worldwide. Uniquely among SI base units, the kilogram is named with a metric prefix ("kilo-" = 1,000).
The grain is among the oldest measurement units in history, derived from the average weight of a grain of barleycorn (or wheat) — a practical standard used in ancient Egypt, Greece, and Rome. England formalised the barleycorn grain in the 15th century as the foundation of its weight system. The British Weights and Measures Act 1824 defined the grain, and the value remains unchanged today.
Interesting fact: The original grain was calibrated by laying dried barleycorns end-to-end — 32 grains equalled one inch in 13th-century England. Today, 9mm pistol bullets typically weigh 115–147 grains (7.5–9.5 g), and gunpowder charges are specified in grains for reloading.
Defined in 1795 by the French Revolutionary government as the mass of one cubic decimetre of distilled water at 4 °C. A platinum prototype (the Kilogramme des Archives) was created in 1799. From 1889 until 2019, the world's mass standard was the International Prototype Kilogram — a platinum-iridium cylinder stored in Sèvres, France. In 2019, the kilogram was redefined in terms of Planck's constant (h = 6.626 070 15 × 10⁻³⁴ J·s), eliminating the need for a physical artifact.
Interesting fact: The IPK and its official copies drifted apart by up to 50 micrograms over 130 years, motivating the 2019 redefinition. The kilogram is the only SI unit whose name starts with a prefix.