The Nuclear Explosion Simulator is a free online tool that lets you visualize the blast radius of nuclear detonations on any city or location worldwide. Select from historical warheads like Little Boy (15 kt) or modern weapons like the W-88 (475 kt), and see the fireball, air blast, thermal radiation, and fallout zones overlaid on a real map. Used by educators and curious minds, the simulator has been accessed millions of times to understand nuclear weapons effects.
Choose any location on the interactive global map by searching for a city or clicking directly. Select a warhead type and yield, then detonate to see concentric damage zones rendered in real time. The simulator calculates fireball radius, severe blast damage, moderate blast damage, thermal radiation range, and fallout patterns using established nuclear effects scaling laws. You can compare different warhead sizes and see how geography affects the impact.
The Nuclear Explosion Simulator lets you visualize the blast radius of various nuclear warheads on any city. Effects depend on the warhead yield and include a fireball, air blast causing structural damage, thermal radiation causing burns, and radioactive fallout. A 15-kiloton bomb (Hiroshima-size) would cause severe destruction within roughly 1.6 km.
Blast radius varies by warhead yield. A 15-kiloton weapon (like Hiroshima) has a severe damage radius of about 1.6 km. A modern 800-kiloton warhead creates a fireball nearly 1 km wide and causes third-degree burns up to 10 km away. The Tsar Bomba (50 megatons) had a thermal radiation radius exceeding 60 km.
The simulator uses established nuclear weapons effects models based on publicly available data, including scaling laws for blast overpressure, thermal radiation, and fireball size. While it provides a realistic approximation, real-world effects depend on many variables including terrain, weather, altitude of detonation, and building construction.
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Last updated: March 2026 · whatifs.fun — Free interactive games, experiments & simulations