W76
USA · 1978 · 90 kilotons · thermonuclear (hydrogen bomb)
Overview
Common SLBM warhead (W76-0 from 1978; current W76-1 ~90 kt from 2008; W76-2 ~8 kt).
With a yield of 90 kilotons[1, 2], the W76 is 6× more powerful than the Hiroshima bomb. As a thermonuclear (hydrogen bomb) weapon, it derives its energy from a fission explosion that ignites fusion fuel, releasing on average roughly equal energy from fission and fusion. [3]
W76 Blast Effects
The table below shows the calculated radius of each effect zone for an air burst at optimum height. Values are scaling laws from The Effects of Nuclear Weapons (Glasstone & Dolan, 1977) and the published effects scaling table[4, 5].
| Effect zone | Radius (air burst) |
|---|---|
| Fireball radius | 0.37 km |
| Severe blast (20 psi) | 1.02 km |
| Moderate blast (5 psi) | 2.80 km |
| Light blast (1 psi) | 7.70 km |
| 3rd-degree thermal burns | 4.57 km |
| 2nd-degree thermal burns | 5.80 km |
| 1st-degree thermal burns | 7.50 km |
All radii assume an air burst at optimum height and are 1-D ground-distance estimates from the detonation point. Real-world effects depend on terrain, weather, and building construction. Casualty and fallout estimates are not shown pending a verified population and fallout model.
Run the W76 on a City
Use the interactive simulator to detonate the W76 on any city worldwide. Click any location on the map to see the fireball, blast, and thermal radii (air burst at optimum height) overlaid on real geography.
🎯 Simulate W76Related Weapons
FAQ
How big is the W76 blast radius?
In an air burst at optimum height, the W76 produces a fireball roughly 0.37 km in radius and a 5 psi moderate-blast zone of about 2.80 km — the area in which most residential buildings would collapse. The 1 psi light-damage radius extends to roughly 7.70 km, where windows shatter.
What is the yield of the W76?
The W76 has a yield of 90 kilotons of TNT equivalent. That is 6× more powerful than the Hiroshima bomb.
Is the W76 bigger than the Hiroshima bomb?
The Hiroshima bomb (Little Boy) had a yield of approximately 15 kilotons. The W76 at 90 kilotons is 6× more powerful than the Hiroshima bomb.[6]
What thermal burn radius does the W76 produce?
In an air burst at optimum height, thermal radiation from the W76 can cause 3rd-degree burns out to roughly 4.57 km, 2nd-degree burns to 5.80 km, and 1st-degree burns to 7.50 km.
Sources
- 1.Source: Bulletin of the Atomic Scientists / FAS (Kristensen, Korda, Johns, Knight-Boyle), United States nuclear weapons, 2026 (Nuclear Notebook, 12 Mar 2026) — retrieved Oct 2026
- 2.Source: Nuclear Weapon Archive (Carey Sublette), Complete List of All U.S. Nuclear Weapons (last changed 30 Mar 2023) — retrieved Oct 2026
- 3.Source: US DoD & ERDA (Glasstone & Dolan), via Atomic Archive, The Effects of Nuclear Weapons, 3rd ed. (1977), Chapter 1 — retrieved Oct 2026
- 4.Source: U.S. DoD / DOE (Glasstone & Dolan, via Atomic Archive), The Effects of Nuclear Weapons, 3rd ed. (1977) §2.127 — retrieved Oct 2026
- 5.Source: Wikipedia, Effects of nuclear explosions — scaling-law table — retrieved Oct 2026
- 6.Source: US DOE / NNSA Nevada Field Office, United States Nuclear Tests, July 1945 through September 1992 (DOE/NV-209 Rev. 16, Sep 2015), NNSS publication library — retrieved Oct 2026