Earthquakes in Japan — June 2025

88 earthquakes were recorded in Japan during June 2025, an average of 2.9 per day.

88 reached magnitude 4 or above and 12 reached magnitude 5 or above. The average focal depth was 54 km.

The month's largest event in Japan was a magnitude 6.1 earthquake near Nemuro, Japan on 21 June 2025 at 21:23 UTC. A magnitude 6.1 earthquake radiates roughly 21,301 tons of TNT equivalent in seismic energy.

That is well above the Japan monthly average of 57 events over the period we cover — an unusually active month, and up from the 47 recorded the previous month.

83% of events here are shallow (under 70 km), 11% intermediate (70–300 km) and 6% 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 76 in the magnitude 4 range, 11 in the magnitude 5 range, 1 in the magnitude 6 range.

Activity peaked on 22 June, when 13 events were recorded.

The month's largest events were M6.1 near Nemuro, Japan on 21 June at 10 km; M5.9 near Nemuro, Japan on 18 June at 13 km; M5.8 near Hiroo, Japan on 01 June at 27 km.

That is 55% above the 57 events Japan averages per month across the 21 months on record.