grain to milligram
Convert grain (gr) to milligram (mg). Use an editable mass converter, conversion formula, and reference table.
1 gr = 64.79891 mg
Conversion formula
One grain equals 64.79891 milligram. Multiply your value in grain by this factor to get milligram. For the reverse conversion, divide by the same factor.
Worked example
To convert 5 grain:5 × 64.79891 = 323.99455 mg
Conversion table
| grain (gr) | milligram (mg) |
|---|---|
| 0.01 | 0.6479891 |
| 0.1 | 6.479891 |
| 1 | 64.79891 |
| 2 | 129.59782 |
| 5 | 323.99455 |
| 10 | 647.9891 |
| 25 | 1,619.97275 |
| 50 | 3,239.9455 |
| 100 | 6,479.891 |
| 1000 | 64,798.91 |
About these measurements
Mass quantifies an amount of matter.
The base reference used here is the gram. One grain is 0.06479891 base units; one milligram is 0.001 base units.
Important distinctions
Mass is not force. Avoirdupois ounces and troy ounces have different masses.
Precision
The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.
Common questions
How do I convert gr to mg?
Multiply the quantity in gr by 64.79891. You can also type the value into the converter above.
Can I reverse the conversion?
Yes. Use the swap button or open the milligram to grain converter.
Reference
NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.
