Convert Gigajoules to Megatons of TNT
Convert Gigajoules (GJ) to Megatons of TNT (Mt(TNT)) instantly and accurately.
Conversion Formula
Mt(TNT) = GJ × 2.390057361e-7
About Gigajoules
A gigajoule (GJ) is 10⁹ J - the scale of fossil-fuel commodity volumes. One barrel of crude oil contains ~5.80 GJ; one metric tonne of hard coal ~29.3 GJ. Canadian energy bills express household consumption in GJ: average Canadian households use ~100-130 GJ/year. A 1 GW power plant at 33% efficiency burns ~10.9 GJ/h of fuel to generate 1 GWh = 3.6 GJ of electricity. Detonation of 1 tonne of TNT releases 4.184 GJ. 1 GJ = 10⁹ J = 277.78 kWh = 947,817 BTU = 9.4782 therms.
About Megatons of TNT
A megaton of TNT (Mt(TNT)) = 10⁶ tons of TNT = exactly 4.184 PJ. The Soviet Tsar Bomba (1961) yielded ~50 Mt - the largest human-made explosion ever, with a fireball 8 km in diameter. Castle Bravo (1954) yielded ~15 Mt, 2.5× its 6 Mt design yield. Modern thermonuclear warheads typically range from 0.1-1.2 Mt. The 2011 Tōhoku earthquake released ~500 Mt in seismic energy. The Krakatoa 1883 eruption released ~200 Mt; Tambora 1815 ~33,000 Mt. 1 Mt(TNT) = 4.184 PJ = 1,162,800 MWh.
Quick Reference Table
| Gigajoules (GJ) | Megatons of TNT (Mt(TNT)) |
|---|---|
| 1 GJ | 2.39 × 10-7 Mt(TNT) |
| 2 GJ | 4.78 × 10-7 Mt(TNT) |
| 5 GJ | 1.195 × 10-6 Mt(TNT) |
| 10 GJ | 2.39 × 10-6 Mt(TNT) |
| 25 GJ | 5.975 × 10-6 Mt(TNT) |
| 50 GJ | 1.195 × 10-5 Mt(TNT) |
| 100 GJ | 2.39 × 10-5 Mt(TNT) |