Tsar Bomba vs Little Boy
Nuclear weapon side-by-side comparison
Verdict
The Tsar Bomba is 3,333× more powerful than the Little Boy by yield. Both weapons are detailed below, with side-by-side blast and thermal radii for an air burst.
Blast & thermal radii (air burst)
| Effect zone | Tsar Bomba | Little Boy |
|---|---|---|
| Yield | 50 megatons | 15 kilotons |
| Fireball radius | 4.62 km | 0.18 km |
| Severe blast (20 psi) | 8.64 km | 0.54 km |
| Moderate blast (5 psi) | 23.1 km | 1.54 km |
| Light blast (1 psi) | 64.1 km | 4.26 km |
| 3rd-degree thermal burns | 54.1 km | 2.18 km |
| 2nd-degree thermal burns | 61.2 km | 2.80 km |
Air burst at optimum height, computed by the site's effects engine. [3, 4] Casualty and fallout estimates are withdrawn pending a verified model.
Hiroshima reference
The Hiroshima bomb (Little Boy) had a yield of approximately 15 kilotons. [2] The Tsar Bomba is 3,333× more powerful than the Hiroshima bomb. The Little Boy is the Hiroshima bomb.
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FAQ
Is the Tsar Bomba bigger than the Little Boy?
Yes. The Tsar Bomba (50 megatons) is 3,333× more powerful than the Little Boy (15 kilotons) by yield.
What is the blast radius of the Tsar Bomba compared to the Little Boy?
For an air burst at optimum height, the Tsar Bomba produces a 5 psi moderate-blast radius of 23.1 km, versus 1.54 km for the Little Boy. Severe blast (20 psi): 8.64 km vs 0.54 km. 3rd-degree thermal burns: 54.1 km vs 2.18 km.
How do the Tsar Bomba and Little Boy compare to the Hiroshima bomb?
The Hiroshima bomb (Little Boy) was about 15 kt. The Tsar Bomba is 3,333× more powerful than the Hiroshima bomb. The Little Boy is the Hiroshima bomb.
Sources
- 1.Source: Nuclear Weapon Archive (Carey Sublette), Soviet Atmospheric Tests (last updated 7 Oct 1997) — retrieved Oct 2026
- 2.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
- 3.Source: U.S. DoD / DOE (Glasstone & Dolan, via Atomic Archive), The Effects of Nuclear Weapons, 3rd ed. (1977) §2.127 — retrieved Oct 2026
- 4.Source: Wikipedia, Effects of nuclear explosions — scaling-law table — retrieved Oct 2026