A magnitude 4.6 earthquake near Fontana, San Bernardino County, California, USA, was reported only 39 seconds ago by the United States Geological Survey, considered the key international and national agency that monitors seismic activity in the US. The earthquake occurred at a very shallow depth of 5.6 miles beneath the epicenter in the morning on Thursday, July 31st, 2025, at 9:32 am local time. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review data and refine their calculations, or as other agencies issue their report.Based on the preliminary seismic data, the quake was probably felt by many people in the area of the epicenter. It should not have caused significant damage, other than objects falling from shelves, broken windows, etc. In Fontana (pop. 212,700) located 4 miles from the epicenter, Rialto (pop. 103,100) 5 miles away, San Bernardino (pop. 216,100) 8 miles away, Colton (pop. 54,600) 8 miles away, Rancho Cucamonga (pop. 175,200) 10 miles away, and Upland (pop. 76,400) 13 miles away, the quake should have been felt as light shaking.Weak shaking might have been felt in Riverside (pop. 322,400) located 14 miles from the epicenter, and Ontario (pop. 171,200) 14 miles away.Other towns or cities near the epicenter where the quake might have been felt as very weak shaking include Los Angeles (pop. 3,898,700) located 47 miles from the epicenter.VolcanoDiscovery will automatically update magnitude and depth if these change and follow up if other significant news about the quake become available. If you’re in the area, please send us your experience through our reporting mechanism, either online or via our mobile app. This will help us provide more first-hand updates to anyone around the globe who wants to know more about this quake.Earthquake data: Date & time: Jul 31, 2025 04:32 pm (Universal Time) local time (31 Jul 2025 16:32 GMT)Magnitude: 4.5Depth: 9.00 kmEpicenter latitude / longitude: 34.15°N / 117.42°W (San Bernardino County, California, United States)Primary data source: USGS