Tokyo city centre sits 9.2 km from Tokyo (Kasumigaseki), the most plausible strategic target in the area (high targeting confidence). Modelled strike: 300 kt airburst.
Estimated survival chance at city centre: 92% · Estimated metro fatalities: 535K, injuries: 644.2K
What a strike on Tokyo (Kasumigaseki) would mean
A 300 kt detonation produces a fireball 646 m across in radius. Reinforced concrete fails out to 2.3 km (20 psi). Most residential buildings collapse within 4.6 km (5 psi), and windows shatter dangerously out to 10.4 km (1 psi). Anyone in line of sight within 6.9 km suffers third-degree burns from the thermal pulse.
An airburst maximises blast damage but produces minimal local fallout, so for Tokyo the dominant risks are blast and thermal effects rather than radiation.
Most plausible targets near Tokyo
| Target | Type | Distance | Assumed yield | Confidence |
|---|---|---|---|---|
| Tokyo (Kasumigaseki) | government | 9 km | 300 kt | high |
| Yokota Air Base, Japan | military | 28 km | 300 kt | high |
| Yokosuka Naval Base | military | 43 km | 300 kt | high |
| Haneda, Tokyo | airport | 18 km | 150 kt | medium |
| Misawa Air Base, Japan | military | 579 km | 300 kt | high |
Key blast radii (300 kt airburst)
| Effect | Radius | What happens |
|---|---|---|
| Fireball | 646 m | Complete vaporisation |
| 20 psi blast | 2.3 km | Hardened structures destroyed, ~100% fatalities |
| 5 psi blast | 4.6 km | Most buildings collapse, widespread fatalities |
| 3rd-degree burns | 6.9 km | Full-thickness burns to exposed skin |
| 500 rem radiation | 2.4 km | Lethal dose without medical care |
| 1 psi blast | 10.4 km | Window breakage, light damage, glass injuries |
How Tokyo can prepare
With a population density of 6,400 people/km², Tokyo's outcome would hinge on the first hour. The guidance is identical everywhere: get inside, stay inside, stay tuned. A basement or the core of a large concrete building cuts fallout exposure by a factor of 10 or more, and radiation decays fast — dose rates fall ~90% within the first 7 hours and ~99% within two days.
Check your exact address in Tokyo →