Convert Grains to Kilotonnes
Convert Grains (gr) to Kilotonnes (kt) instantly and accurately.
Conversion Formula
kt = gr × 6.479891000e-11
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 Kilotonnes
A kilotonne (kt) equals 1,000 metric tonnes (10⁶ kg). In military and geopolitical contexts, nuclear weapon yields are expressed in kilotons of TNT equivalent (kt TNT): the atomic bomb dropped on Hiroshima had a yield of approximately 15 kt TNT. Environmental science uses kilotonnes for reporting regional greenhouse gas inventories, industrial pollutant releases, and annual waste generation. Mining operations quote ore extraction rates in kilotonnes per day. The global atmospheric inventory of various trace gases is reported in kilotonnes.
Quick Reference Table
| Grains (gr) | Kilotonnes (kt) |
|---|---|
| 1 gr | 6.48 × 10-11 kt |
| 2 gr | 1.296 × 10-10 kt |
| 5 gr | 3.24 × 10-10 kt |
| 10 gr | 6.48 × 10-10 kt |
| 25 gr | 1.62 × 10-9 kt |
| 50 gr | 3.24 × 10-9 kt |
| 100 gr | 6.48 × 10-9 kt |