The best source for information about recent California earthquakes is the website called Maps of Recent Earthquake Activity in California-Nevada, operated by the United States Geological Survey (USGS).
There you'll find a map of California and Nevada with all of the recent earthquakes plotted on the map. Look for a large square for a large recent California earthquake.
Color indicates how recently the earthquake occurred. If the earthquake was within an hour, the square will be red. Within the past day, the square will be blue. Earthquakes that happened more than a day ago but less than a week ago will be yellow.
You then click the square to zoom into a local map. Then, click the square for the largest earthquake you see for a page full of great information about the earthquake. The information will include date and time of the quake, magnitude, location, depth, distance from major cities, latitude and longitude, and more.
One the page, you will also find a Did You Feel It? link for larger earthquakes where you can report how strongly you felt a California earthquake to help scientists and emergency managers.
California Historical Earthquakes
For information about major earthquakes in California history, visit the Recent and Significant Past Earthquakes page, which includes earthquakes around the world but more than half are California earthquakes.
You may also want to visit the California Earthquake History 1769-Present list, which is a simple and straightforward list of all known earthquakes in California larger than magnitude 6.
California Earthquake Preparedness
It is very important to be prepared for earthquakes in California. Be sure to visit the USGS Hazards and Preparedness page to learn about local earthquake risk and how to prepare.