B61 on Paris
340 kt thermonuclear weapon · France · Population 2,165,423 · Density 21,000/km²
About this scenario
This page calculates what would happen if the B61 (USA, 1968) detonated over Paris (France). Variable yield tactical bomb.
The capital of France and one of the most densely populated major cities in Europe; the Île-de-France region holds over 12 million people. With an urban-core density of about 21,000 people per km², even a relatively small detonation over the city center would affect a large population.
The B61 delivers 340 kt of explosive yield — 23× more powerful than the Hiroshima bomb. The tables below show calculated effect radii for an air burst (optimized for blast spread) and a surface burst (which produces massive fallout).
Air-burst effects (B61 over Paris)
| Effect zone | Radius | Est. affected |
|---|---|---|
| Fireball (vaporization, 100% fatal) | 1.49 km | ~146,990 |
| Severe blast (20 PSI, ~98% fatal) | 3.30 km | ~556,836 |
| Moderate blast (5 PSI, ~50% fatal) | 7.05 km | ~1,280,701 |
| Light blast (1 PSI, glass injuries) | 20.06 km | ~1,162,958 |
| 3rd-degree thermal burns | 7.31 km | — |
| 2nd-degree thermal burns | 13.09 km | — |
Estimated total fatalities: ~1,984,527 · Estimated total affected (inside 1 PSI light-blast radius): ~26,538,752.
Surface-burst effects (with fallout)
A surface burst trades blast spread for radioactive fallout — much smaller blast radii but a large lethal fallout plume drifting downwind. This is what would happen if the B61 struck ground level rather than detonating optimally above Paris.
| Effect zone | Radius (surface burst) |
|---|---|
| Fireball | 1.19 km |
| Severe blast (20 PSI) | 1.81 km |
| Moderate blast (5 PSI) | 3.88 km |
| Light blast (1 PSI) | 11.03 km |
| 3rd-degree thermal burns | 4.39 km |
| Lethal fallout zone | ~123.5 km |
Run this scenario in the simulator
See the actual blast zones overlaid on a map of Paris with population-density-based casualty estimates updated in real time as you move the detonation point.
🎯 Open this scenario on the mapB61 on other cities
Other weapons on Paris
FAQ
What would happen if the B61 detonated over Paris?
In an air burst over Paris, the B61 (340 kt) would produce a fireball about 1.49 km in radius. The 5 PSI moderate-blast zone — where most residential buildings collapse — would extend to 7.05 km. Light blast damage and shattered windows would reach 20.06 km. Given Paris's urban density (~21,000/km²), this scenario yields an estimated 1,984,527 immediate fatalities and about 1,162,958 additional injured.
How many people would die in Paris from a B61 strike?
An air burst of the B61 over Paris could cause an estimated 1,984,527 immediate fatalities and 1,162,958 additional injuries. The fireball alone (radius 1.49 km) would kill approximately 146,990 people; the severe-blast zone (20 PSI, radius 3.30 km) would add 556,836; the moderate-blast zone (5 PSI, radius 7.05 km) would add 1,280,701 more. Real numbers depend heavily on time of day, sheltering, weather, and altitude of detonation.
What is the blast radius of the B61 on Paris?
For an air burst over Paris: fireball 1.49 km, severe blast (20 PSI) 3.30 km, moderate blast (5 PSI) 7.05 km, light blast (1 PSI) 20.06 km. Thermal radiation causes 3rd-degree burns out to 7.31 km. A surface burst would shrink the blast radii by roughly 40 percent but generate massive radioactive fallout extending ~124 km from ground zero.
Is the B61 bigger than the bomb that hit Hiroshima?
The Hiroshima bomb (Little Boy) had a yield of about 15 kilotons. The B61 at 340 kt is 23× more powerful than the Hiroshima bomb.