Earthquakes in Tokyo
Tokyo is one of the world's most earthquake-prone megacities, sitting above a complex zone where three tectonic plates interact. The metropolitan area of 37 million people experiences hundreds of minor tremors each year and faces the long-anticipated threat of a major Nankai Trough megathrust earthquake or a shallow inland fault rupture beneath the city itself.
Why Does Tokyo Face Earthquake Risk?
Tokyo sits at the convergence of the Pacific, Philippine Sea, and Eurasian plates. The Philippine Sea Plate subducts beneath Tokyo at approximately 3-4 cm per year, regularly generating moderate earthquakes felt by the city. A major fault system also runs directly beneath the Tokyo metropolitan area. Government studies estimate a 70% probability of a magnitude 7 earthquake directly beneath Tokyo within 30 years — an event that could cause devastating fires and structural damage.
Active Fault Systems
- North Anatolian Fault
- Philippine Sea Plate Subduction Zone
- Tachikawa Fault
Safety Advice
Tokyo's earthquake early warning system provides seconds to minutes of advance notice before shaking arrives. Download the Earthquake Globe app for real-time alerts. Know your nearest evacuation area — Tokyo has over 200 designated earthquake evacuation sites. Many older wooden neighborhoods in eastern Tokyo remain vulnerable to fire following a major earthquake.
Historical Earthquake Context
The 1923 Great Kantō earthquake (M7.9) killed 140,000 people and leveled much of Tokyo. The earthquake and subsequent fires destroyed 90% of the city's wooden structures. Tokyo has since transformed into one of the world's most earthquake-resilient cities through decades of investment in seismic engineering and urban planning.
Fault Maps & Tectonic Setting
Tectonic and seismic hazard maps from Wikimedia Commons, USGS, and NASA — open licenses (CC / Public Domain)
Maps sourced from Wikimedia Commons, USGS, and NASA under open licenses. Attribution required where specified. Click any map to enlarge.
FAQ
Frequently Asked Questions
Is Tokyo safe from earthquakes?
Tokyo is one of the world's most earthquake-prepared cities, with strict building codes and comprehensive early warning systems. However, a major earthquake directly beneath the city remains a recognized threat. Modern buildings in Tokyo are generally safe; older wooden structures in eastern neighborhoods carry greater risk.
What was the worst earthquake in Tokyo history?
The 1923 Great Kantō earthquake (M7.9) is the worst earthquake in Tokyo's history, killing 140,000 people when fires swept the city after the earthquake collapsed thousands of wooden buildings and ruptured gas lines.
How can I get earthquake alerts for Tokyo?
Japan's J-Alert system broadcasts earthquake warnings via TV, radio, and mobile phones. Download Earthquake Globe for real-time magnitude alerts filtered by your threshold and location near Tokyo.
What magnitude earthquake could hit Tokyo?
Government studies estimate a 70% probability of a direct M7.0+ earthquake beneath Tokyo within 30 years. The long-anticipated Nankai Trough megathrust event could reach M9.0 and generate severe shaking in Tokyo even though its epicenter would be offshore. A M8-class Sagami Trough event also poses a recognized threat.
What should I do during an earthquake in Tokyo?
Drop, Cover, and Hold On. Tokyo's earthquake early warning system (EEW) may give you seconds of advance notice via your phone. After shaking stops, exit using stairs (not elevators), check for gas leaks, and proceed to your nearest designated evacuation area (hinanbasho). Do not use roads needed for emergency vehicles.
Explore More
Get Earthquake Alerts for Tokyo
Earthquake Globe sends real-time push notifications filtered by magnitude and location. Free on the App Store.
iOS 16+ · iPhone & iPad · No subscription required