Convert Grains to Gigatons
Convert Grains (gr) to Gigatons (Gt) instantly and accurately.
Conversion Formula
Gt = gr × 6.479891000e-17
About Grains
A grain (gr) is the smallest unit in both the avoirdupois and troy weight systems, equal to exactly 64.79891 milligrams. Originally defined as the mass of a single grain of barley or wheat from the middle of an ear, it has been a standard of weight since ancient times. Today, grains are used to weigh gunpowder charges and bullets (a standard .308 rifle bullet weighs 168 gr), pharmaceutical preparations in apothecary compounding, and the fineness of gold alloys. Arrowhead and fishing hook weights are also specified in grains.
About Gigatons
A gigaton (Gt) equals one billion metric tonnes (10¹² kg). It is the standard unit for planetary-scale mass measurements and global environmental budgets. Annual human CO₂ emissions are approximately 37 Gt CO₂; Earth's atmosphere contains roughly 5,480 Gt of air; Antarctic ice sheet mass is around 26,500,000 Gt of ice. Climate scientists report ice sheet mass balance changes in gigatons per year - the Greenland ice sheet loses approximately 280 Gt of ice annually due to climate change.
Quick Reference Table
| Grains (gr) | Gigatons (Gt) |
|---|---|
| 1 gr | 6.48 × 10-17 Gt |
| 2 gr | 1.296 × 10-16 Gt |
| 5 gr | 3.24 × 10-16 Gt |
| 10 gr | 6.48 × 10-16 Gt |
| 25 gr | 1.62 × 10-15 Gt |
| 50 gr | 3.24 × 10-15 Gt |
| 100 gr | 6.48 × 10-15 Gt |