Earthquakes in Japan — April 2025

42 earthquakes were recorded in Japan during April 2025, an average of 1.4 per day.

42 reached magnitude 4 or above and 5 reached magnitude 5 or above. The average focal depth was 79 km.

The month's largest event in Japan was a magnitude 6.2 earthquake near Nishinoomote, Japan on 02 April 2025 at 14:03 UTC. A magnitude 6.2 earthquake radiates roughly 30,089 tons of TNT equivalent in seismic energy.

That is below the Japan monthly average of 57 events over the period we cover — a comparatively quiet month, and up from the 40 recorded the previous month.

76% of events here are shallow (under 70 km), 17% intermediate (70–300 km) and 7% deep-focus (over 300 km). That proportion of deep-focus events is the signature of a subduction zone: only a cold slab descending into the mantle stays brittle enough to rupture at those depths.

By band, the catalogue holds 37 in the magnitude 4 range, 4 in the magnitude 5 range, 1 in the magnitude 6 range.

Activity peaked on 01 April, when 4 events were recorded.

The month's largest events were M6.2 near Nishinoomote, Japan on 02 April at 26 km; M5.4 near Yonakuni, Japan on 08 April at 124 km; M5.2 near Ōmachi, Japan on 18 April at 10 km.

That is 26% below the 57 events Japan averages per month across the 21 months on record.