On Thursday Night a Significant M5.5 Earthquake struck near Asahi in Japan.

Written by Earthquakelist.org on October 28th, 2026.

A significant M5.5 earthquake struck under land 5 kilometer from Asahi in Japan just after midnight of Thursday October 29th, 2026. The earthquake struck near a very densely populated region. Around 24 million people have been exposed to shaking.

Earthquake Summary

The earthquake struck on land in Japan, 5 kilometer (3 mi) east of Asahi in Chiba. The center of this earthquake had a quite shallow depth of 41 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Oct 29, 2026 00:07 (Tokyo Time) - Oct 28, 2026 15:07 Universal Time.
Location:	5 km east of Asahi, Chiba, Japan. Coordinates 35°42'5"N 140°42'21"E.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 5.5 Detected by 24 stations. Maximum Error Range ±0.063 .
Depth:	41 km (26 mi) A quite shallow depth.
Max. Intensity:	V Moderate On the Modified Mercalli Scale.
Tsunami Risk:	Tsunami very unlikely While this was a shallow earthquake in a coastal area, it appears to have occurred under land (0 km from the sea) with a magnitude that is usually not strong enough to cause tsunami's. Always stay cautious - More info here.

Minimal impact predicted

Based on scientific estimates by the US Geographic Survey (USGS), the risk of high fatalities for this earthquake is classified at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 fatalities.

The USGS classifies the economic impact of this earthquake at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 million US Dollars in economic damage and impact.

Roughly 24 million people exposed to shaking

This earthquake may have been felt by around 24 million people. That is the expected population size of the area exposed to a level of shaking of II or higher on the Modified Mercalli scale according to the USGS.

An estimated 116,300 people were exposed to level V. At this level, moderate shaking and very light damage can be expected. Intensity level IV was experienced by the majority of people (around 23 million). In their region, light shaking and likely no damage can be expected. All exposure to shaking was within the borders of Japan .

People	MMI Level	Shaking	Damage
0	I	Not noticable	None
0	II	Very weak	None
1,506,000	III	Weak	Probably none
22,730,000	IV	Light	Likely none
116,300	V	Moderate	Very light
0	VI	Strong	Light
0	VII	Very Strong	Moderate
0	VIII	Severe	Moderate to heavy
0	IX	Violent	Heavy
0	X	Extreme	Very heavy

Nearby towns and cities

This earthquake may have been felt in Japan . Asahi in Chiba, Japan is the nearest significant place from the epicenter. The earthquake occurred 5 kilometer (3 mi) east of Asahi. The intensity of shaking and damage in Asahi is estimated to be around level V on the Modified Mercalli Intensity scale (moderate shaking, very light damage).

Multiple major population centers exist within 300km of the earthquake that struck today. Tokyo is located 92 km to the west and experienced an intensity of IV (light shaking, likely no damage). Yokohama is located 100 km to the west and experienced an intensity of IV (light shaking, likely no damage). Chiba is located 54 km to the west and experienced an intensity of IV (light shaking, likely no damage).

A complete list of nearby places is included below. Estimated intensity data (MMI) sourced from a shake-map published by the US Geographic Survey is shown where available (cities without data probably experienced little impact).

Overview of nearby places

Cities and Towns around the epicenter of this earthquake.
Distance	Place	Intensity (MMI)
5 km (3 mi) W from epicenter	Asahi Chiba, Japan.	V Moderate
12 km (7 mi) E from epicenter	Hasaki Chiba, Japan.	IV Light
14 km (9 mi) W from epicenter	Yōkaichiba Chiba, Japan.	IV Light
18 km (11 mi) NW from epicenter	Omigawa Chiba, Japan.	V Moderate
27 km (17 mi) NW from epicenter	Sawara Chiba, Japan.	IV Light
28 km (17 mi) SW from epicenter	Narutō Chiba, Japan.	IV Light
29 km (18 mi) NW from epicenter	Katori-shi Chiba, Japan.	IV Light
29 km (18 mi) NW from epicenter	Itako Ibaraki, Japan.	IV Light
30 km (19 mi) N from epicenter	Kashima-shi Ibaraki, Japan.	IV Light
35 km (22 mi) SW from epicenter	Tōgane Chiba, Japan.	IV Light
36 km (22 mi) W from epicenter	Yachimata Chiba, Japan.	IV Light
36 km (22 mi) W from epicenter	Narita Chiba, Japan.	IV Light
40 km (25 mi) W from epicenter	Shisui Chiba, Japan.	IV Light
41 km (25 mi) SW from epicenter	Ōami Chiba, Japan.	IV Light
43 km (27 mi) W from epicenter	Sakura Chiba, Japan.	IV Light
45 km (28 mi) NW from epicenter	Inashiki Ibaraki, Japan.	IV Light
48 km (30 mi) SW from epicenter	Mobara Chiba, Japan.	IV Light
49 km (30 mi) W from epicenter	Yotsukaidō Chiba, Japan.	IV Light
52 km (32 mi) NW from epicenter	Ryūgasaki Ibaraki, Japan.	IV Light
54 km (34 mi) W from epicenter	Chiba Chiba, Japan.	IV Light
59 km (37 mi) NW from epicenter	Ami Ibaraki, Japan.	IV Light
59 km (37 mi) W from epicenter	Shiroi Chiba, Japan.	IV Light
59 km (37 mi) NW from epicenter	Ushiku Ibaraki, Japan.	IV Light
60 km (37 mi) W from epicenter	Ichihara Chiba, Japan.	IV Light
60 km (37 mi) W from epicenter	Toride Ibaraki, Japan.	IV Light
62 km (39 mi) NW from epicenter	Naka Ibaraki, Japan.	IV Light
65 km (40 mi) W from epicenter	Honchō Chiba, Japan.	IV Light
65 km (40 mi) W from epicenter	Abiko Chiba, Japan.	IV Light
68 km (42 mi) W from epicenter	Kashiwa Chiba, Japan.	IV Light
73 km (45 mi) W from epicenter	Matsudo Chiba, Japan.	IV Light
74 km (46 mi) W from epicenter	Nagareyama Chiba, Japan.	IV Light
74 km (46 mi) W from epicenter	Urayasu Tokyo, Japan.	IV Light
76 km (47 mi) N from epicenter	Mito Ibaraki, Japan.	IV Light
77 km (48 mi) N from epicenter	Katsuta Ibaraki, Japan.	IV Light
78 km (48 mi) NW from epicenter	Tsukuba Ibaraki, Japan.	IV Light
78 km (48 mi) SW from epicenter	Kisarazu Chiba, Japan.	IV Light
79 km (49 mi) N from epicenter	Hitachi-Naka Ibaraki, Japan.	IV Light
79 km (49 mi) W from epicenter	Yashio Saitama, Japan.	IV Light
80 km (50 mi) W from epicenter	Noda Chiba, Japan.	IV Light
83 km (52 mi) W from epicenter	Sōka Saitama, Japan.	IV Light
85 km (53 mi) W from epicenter	Koshigaya Saitama, Japan.	IV Light
85 km (53 mi) SW from epicenter	Kimitsu Chiba, Japan.	IV Light
91 km (57 mi) W from epicenter	Kawaguchi Saitama, Japan.	IV Light
92 km (57 mi) W from epicenter	Kasukabe Saitama, Japan.	IV Light
92 km (57 mi) W from epicenter	Tokyo Tokyo, Japan.	IV Light
92 km (57 mi) W from epicenter	Kawasaki Kanagawa, Japan.	IV Light
93 km (58 mi) W from epicenter	Shimotoda Saitama, Japan.	IV Light
97 km (60 mi) W from epicenter	Saitama Saitama, Japan.	IV Light
100 km (62 mi) W from epicenter	Yokohama Kanagawa, Japan.	IV Light
100 km (62 mi) W from epicenter	Asaka Saitama, Japan.
100 km (62 mi) N from epicenter	Hitachi Ibaraki, Japan.	III Weak
121 km (75 mi) NW from epicenter	Utsunomiya Tochigi, Japan.	III Weak
151 km (94 mi) N from epicenter	Iwaki Fukushima, Japan.
165 km (103 mi) NW from epicenter	Maebashi Gunma, Japan.
193 km (120 mi) W from epicenter	Fuji Shizuoka, Japan.
193 km (120 mi) W from epicenter	Kōfu Yamanashi, Japan.
250 km (155 mi) NW from epicenter	Nagano Nagano, Japan.
283 km (176 mi) N from epicenter	Yamagata Yamagata, Japan.
286 km (178 mi) N from epicenter	Sendai Miyagi, Japan.
286 km (178 mi) NW from epicenter	Niigata Niigata, Japan.
291 km (181 mi) W from epicenter	Nakatsugawa Gifu, Japan.

Earthquake Intensity Map

The intensity in shaking and damage by this earthquake is illustrated through the map below. The highest intensity measured for this earthquake is V.

I Not felt

II Weak

III Weak

IV Light

V Moderate

VI Strong

VII Very Strong

VIII Severe

IX Violent

X Extreme

Earthquake Intensity Map based on Shakemap Data provided by USGS.

Shaking reported by 44 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 44 people have reported shaking in 23 places, all within Japan.We keep updating this article as more ground reports become available. You may report that you felt this earthquake here.

Places with most reports:

Tokyo, Tokio, Japan: 13 people.
Kawasaki, Kanagawa, Japan: 4 people.
Yokohama, Kanagawa, Japan: 3 people.
Narita, Chiba, Japan: 3 people.
Naka, Ibaraki, Japan: 2 people.
Hakone, Kanagawa, Japan: 2 people.
Asahi, Chiba, Japan: 1 person.
Higashimurayama, Tokio, Japan: 1 person.
Shibukawa, Gumma, Japan: 1 person.
Kaminokawa, Tochigi, Japan: 1 person.

2 Aftershocks detected

Since this main shock, 2 smaller aftershocks were detected. At a distance of 10 km (6 mi) northwest of this earthquake, an aftershock struck 3 hrs later. It measured a magnitude of 4.7

This main shock was prefaced by 1 smaller foreshock. Nearby this earthquake a foreshock struck 2 days earlier. It measured a magnitude of 3.1

Overview of foreshocks and aftershocks

Detected MAG2.5+ earthquakes within within 100km (62 mi), that occurred in the three days before and after the main shock.
Classification	Magnitude	When	Where
Foreshock	M 3.1	2 days earlier Oct 26, 2026 13:37 (Tokyo Time)	11 km (7 mi) N from Main Shock.
Main Shock This Earthquake	M 5.5	Oct 29, 2026 00:07 (Tokyo Time)	-
Aftershock	M 4.7	3 hrs later Oct 29, 2026 03:32 (Tokyo Time)	10 km (6 mi) NW from Main Shock.
Aftershock	M 3.5	5 hrs later Oct 29, 2026 05:22 (Tokyo Time)	0.6 km (0.4 mi) W from Main Shock.

More earthquakes coming?

Aftershocks are usually at least 1 order of magnitude less strong than main shocks. The more time passes, the smaller the chance and likely strength of any potential aftershocks.

The chance that a significant earthquake like this one is followed by an even larger earthquake is not so large. On average, scientists estimate a 94% chance that a major earthquake will not be followed by an even larger one. It is still adviced to be aware of this risk

Read: How to Stay Safe during an Earthquake (cdc.gov).

Earthquakes like this happen often in the region

Earthquakes of this strength are very common in the region. This is the strongest earthquake to hit since August 22nd, 2026, when a 5.8 magnitude earthquake hit 55 km (34 mi) further northwest. An even stronger magnitude 7.3 earthquake struck on March 16th, 2022.

In total, 42 earthquakes with a magnitude of 5.5 or higher have been registered within 300km (186 mi) of this epicenter in the past 10 years. This comes down to an average of once every 3 months.

Tsunami very unlikely

DISCLAIMER: We strongly suggest to closely monitor advice from local authorities with regards to tsunami risks. Our analysis is based on automatically collected data from external sources, and these might contain mistakes. In addition, earthquakes can cause landslides that may lead to a tsunami, or be a followed by another, potentially stonger, earthquake.

While MAG-6.5+ earthquakes may cause tsunami's, it appears that the epicenter of this earthquake hit under land. In addition, the reported depth is deeper than 100km, making the risk of a tsunami even less likely. However always stay cautious and monitor advice from local authorities.

Tsunami Risk Factors

Factor	Under Sea?	MAG-6.5 or stronger?	Shallow depth?
Explanation	Almost all tsunami's are caused by earthquakes with their epicenter under sea or very near the sea. However stay cautious in coastal areas as earthquakes on land may cause landslides into sea, potentially still causing a local tsunami.	Under MAG 6.5: Very unlikely to cause a tsunami. MAG 6.5 to 7.5: Destructive tsunami's do occur, but are uncommon. Likely to observe small sea level changes. MAG 7.6+: Earthquakes with these magnitudes might produce destructive tsunami's.	Most destructive tsunami's are caused by shallow earthquakes with a depth between 0 and 100km under the surface of the earth. Deeper tsunami's are unlikely to displace to ocean floor.
This Earthquake	This earthquake appears to have struck on land near a coastal area (0 km from the sea).	Not this earthquake. This earthquake had a magnitude of 5.5. Earthquakes of this strength are unlikely to trigger a tsunami.	This earthquake occurred at a depth of of 41 km (26 mi). Earthquakes this shallow could trigger a tsunami.

Sources

Last updated 28/10/26 21:58 (). This article contains currently available information about the earthquake and is automatically composed. We continue to update this article up to a few days after the earthquake occurred.