Convert Joules to Megatons of TNT
Convert Joules (J) to Megatons of TNT (Mt(TNT)) instantly and accurately.
Conversion Formula
Mt(TNT) = J × 2.390057361e-16
About Joules
The joule (J) is the SI unit of energy, defined as one newton acting through one metre (1 J = 1 N·m = 1 kg·m²/s²). Named after James Prescott Joule, whose 1840s paddle-wheel experiments established the mechanical equivalent of heat (~4.15 J = 1 calorie). One joule is modest: it lifts a 100 g apple by 1 m, heats 0.239 mL of water by 1°C, or powers a 1 W LED for 1 second. Daily adult resting metabolism is ~6-9 MJ. 1 J = 1 W·s = 0.23901 cal = 9.4782 × 10⁻⁴ BTU = 2.7778 × 10⁻⁷ kWh.
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
| Joules (J) | Megatons of TNT (Mt(TNT)) |
|---|---|
| 1 J | 2.39 × 10-16 Mt(TNT) |
| 2 J | 4.78 × 10-16 Mt(TNT) |
| 5 J | 1.195 × 10-15 Mt(TNT) |
| 10 J | 2.39 × 10-15 Mt(TNT) |
| 25 J | 5.975 × 10-15 Mt(TNT) |
| 50 J | 1.195 × 10-14 Mt(TNT) |
| 100 J | 2.39 × 10-14 Mt(TNT) |