Originally defined as the absolute weight of a volume of pure water equal to the cube of the hundredth part of a metre [1 cm3], and at the temperature of melting ice
									
However, in a reversal of reference and defined units, a gram is now defined as one thousandth of the SI base unit, the kilogram, or 1×10−3kg, which itself is defined by the International Bureau of Weights and Measures, not in terms of grams, but by taking the fixed numerical value of the Planck constant h to be 6.62607015×10−34 kgm2s−1
                                
g
 1 gram (g) = 15.4323583529 grains (gr)
 1 grain (gr) = 0.06479891 grams (g)
									
| Standard Units | |
|---|---|
| Carats (ct) | |
| Kilograms (kg) | {{kg}} | 
| Metric Tons (t) | {{t}} | 
| Micrograms | {{micrograms}} | 
| Milligrams | {{mg}} | 
| Ounces (oz) | {{oz}} | 
| Pounds (lb) | {{lb}} | 
| Other Units | |
| Grain (gr) | {{gr}} | 
| Pennyweight (dwt) | {{dwt}} | 
| Stones (st) | {{st}} | 
| Troy Ounces (toz) | {{toz}} | 
| Troy Pounds (tlb) | {{tlb}} |