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Educational guide, not an alert service: no live data. Always follow official instructions from JMA, your municipality, police, fire and staff. In an emergency, protect yourself first. Full disclaimer

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Japan alert decoder · 震度速報・震源・震度に関する情報

Seismic intensity information

Information · official rules as of 2026-10-17

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震度速報・震源・震度に関する情報

Seismic intensity information

A report after a quake: where it was, how big (magnitude) and the seismic intensity (shindo, 0-7) measured in each area. Shindo is how strongly the ground shook where you are, not the size of the quake. It also says whether there is a tsunami risk (この地震による津波の心配はありません = no tsunami risk).

What to do now

  1. Check the intensity for your area (see the shindo scale).
  2. If a tsunami warning or advisory is in effect and you are near the coast, move away from the coast now.
  3. Expect aftershocks.

Issued by: JMA. Live status: JMA warnings map (English)JMA earthquake information (English)JMA tsunami information (English)

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Educational guide, not an alert service: no live data. Always follow official instructions from JMA, your municipality, police, fire and staff. In an emergency, protect yourself first.

Data as of 2026-10-17 from official JMA, Cabinet Office, Cabinet Secretariat (J-ALERT) and Ministry of the Environment pages, with official names from the JMA multilingual dictionary (2026-03-26). Not affiliated with JMA or any government agency.

Educational guide, not an alert service: no live data. Always follow official instructions from JMA, your municipality, police, fire and staff. In an emergency, protect yourself first. Data as of 2026-10-17 from official JMA, Cabinet Office, Cabinet Secretariat (J-ALERT) and Ministry of the Environment pages, with official names from the JMA multilingual dictionary (2026-03-26). Not affiliated with JMA or any government agency.