The economy of the State of California is the largest in the United States, with a $4.297 trillion gross state product (GSP) as of 2025. It is the largest sub-national economy in the world. If California were an independent nation, it would rank as the fourth largest economy in the world in nominal terms, behind Germany and ahead of Japan.
California's Silicon Valley is home to some of the world's most valuable technology companies, including Apple, Alphabet, and Nvidia. As of June 2025, 58 of the Fortune 500 companies are headquartered in California.
As both the most populous US state and one of the most climatologically diverse states, the economy of California is varied, with many sizable sectors. The most dominant of these sectors include finance, business services, government and manufacturing. Much of the economic activity is concentrated in the coastal cities, especially Los Angeles, which has a relative focus on media—most notably Hollywood—and the San Francisco Bay Area, which predominantly concentrates on technology. Both cities, along with other major ports such as San Diego, also act as significant trade hubs to and from the United States. Furthermore, California's agriculture industry has the highest output of any U.S. state, with its Central Valley being one of the most productive agricultural regions on Earth, growing over half the country's fruits, vegetables, and nuts. Droughts in California are affecting business and industry in addition to agriculture.
GDP by county This list shows nominal gross domestic product (GDP) by county in millions of US$, in 2022.
Rank(2022) County GDP(million US$) 1 Los Angeles 2 Santa Clara 3 Orange 4 San Diego 5 San Francisco 6 San Mateo 7 Alameda 8 San Bernardino 9 Sacramento 10 Riverside 11 Contra Costa 12 Ventura 13 Kern 14 Fresno 15 San Joaquin 16 Sonoma County 17 Santa Barbara 18 Marin 19 Solano 20 Monterey 21 Placer 22 Stanislaus 23 Tulare 24 San Luis Obispo 25 Santa Cruz 26 Yolo 27 Napa 28 Merced 29 Butte 30 Imperial 31 Shasta 32 El Dorado 33 Kings 34 Madera 35 Humboldt 36 Nevada 37 Sutter 38 Mendocino 39 Yuba 40 Tuolumne 41 San Benito 42 Tehama 43 Lake 44 Siskiyou 45 Amador 46 Colusa 47 Calaveras 48 Inyo 49 Mono 50 Lassen 51 Glenn 52 Plumas 53 Del Norte 54 Mariposa 55 Modoc 56 Trinity 57 Alpine 58 Sierra California
History
California has experienced waves of migration in the past. Once the Treaty of Guadalupe Hidalgo of 1848 was coercively signed with Mexico, the US acquired the future states of California, Nevada, Utah, Arizona, New Mexico as well as the independent territory of Texas the newly acquired territories underwent rapid and extensive development. In 1847, California was controlled (with much difficulty due to deserters leaving to look for gold) by a U.S. Army-appointed military governor and an inadequate force of a little over 600 troops. After the finding of extensive gold deposits in California, the California gold rush started in 1848. Commerce and economic activity in California initially centered around the vastly expanded cities of San Francisco, San Jose, and Sacramento as they scrambled to supply the hordes of gold miners. Meanwhile, Los Angeles initially remained a less populated settlement with fewer than 5,000 residents.
Prior to 1850, the government was judged inadequate and poorly run, and statehood status was sought to start trying to remedy this problem. Due to the California Gold Rush, by 1850 California had grown to have a non-Indian and non-Californio population (about 7,000 Californios were residing in California in 1850) of over 110,000.U.S. 1850 California Census counts 92,597 residents but omits the residents of San Francisco (estimated at 21,000) whose census records were destroyed by fire. Contra Costa County (estimated at 2,000 residents) and Santa Clara County (estimated at 4,000 residents) 1850 records were "lost" and also not included. The total non-Indian (Indians were not counted) population was over 120,000. See: "Historical Statistical Abstracts - U.S. Census Bureau"; [www.census.gov/prod/www/abs/statab.html] Despite a major conflict in the U.S. Congress on the number of slave versus non-slave states, the large, rapid and continuing California population gains and the large amount of gold being exported east gave California enough clout to choose its own extensive boundaries, elect its representatives and senators, write its Constitution, and be admitted to the Union as a free state in 1850 without going through territorial status as required for most other new states.
Soon after gaining statehood in 1850, the state required and paid through taxes for nearly universal elementary school education. Other private schools were founded and are still doing well. In the 1930s California was a leader in the high school movement to educate students beyond elementary school. State-subsidized college educations have a long history in California as well as many private elementary, middle, high schools, colleges and universities. There are three public funded higher education systems in the state: the California State University (CSU) (founded 1857), the University of California (UC) system (founded 1868), and the California Community College System (CCCS) founded in 1967. CSU is the largest university system in the United States. CSU has 23 campuses and eight off-campus centers enrolling 437,000 students with 44,000 faculty members and staff, The University of California was founded in 1868 in Berkeley as a state supported university. As of fall 2011, the University of California has 10 campuses, a combined student body of 234,464 students, 18,896 faculty members, 189,116 staff members, and over 1,600,000 living alumni. The California Community College System consisting of 112 community colleges in 72 community college districts in California has over 1,800,000 students. California also has an extensive private college system of over 133 colleges and universities including California Institute of Technology (Caltech) and Stanford University. (See: List of colleges and universities in California)
About half the settlers coming to California after 1846 came by the wagon trains on the California Trail (a trip of about 140–160 days). The other half came by sea via paddle steamers going to and from the Isthmus of Panama or Nicaragua (about a 40+ day trip). The building of the Panama Railroad in 1855 made this a much more used route especially for passengers. The other main sailing ship route was going around Cape Horn, about a 120-day (via Clippers) or 200 day trip by regular sailing ship. Nearly all freight to California till 1869 took this long route around South America—shipping by ship has nearly always been relatively slow but cheap. Overland shipping was too difficult and took too long for nearly all cargo. The First Transcontinental Telegraph replaced the Pony Express in 1861 and established the first rapid communication with the east coast. The First transcontinental railroad was completed across the future states of Nebraska, Wyoming, Utah and the new states of Nevada (est. 1864) and California in 1869 and cut this trip to about 7 days. This rail link tied California and the rest of the Pacific states firmly into the union and led to much more rapid and profitable commerce between the states. In 1886 the first refrigerated cars on the Southern Pacific Railroad entered operation. The loading of such cars with oranges, at Los Angeles on February 14, 1886, started an economic boom in the citrus industry of Southern California, by making deliveries of perishable fruits and vegetables to the eastern United States possible.
Early farming in the state was primarily concentrated near the coast, and the Sacramento–San Joaquin River Delta in the Central Valley. Winter wheat was an early crop that grew well without irrigation if planted in the fall and harvested in the spring. By the 1880s extensive grape fields for producing wine were being planted in many areas in California. Many of the vine stock originally came from France and other parts of Europe. Starting in the late 1880s, Chinese workers and other laborers were used to construct hundreds of miles of levees throughout the Sacramento–San Joaquin River Delta's waterways in an effort to control flooding, reclaim and preserve flooded land that could be converted into farmland. This area now often grows extensive rice crops. Subsequent irrigation projects have brought many more parts of the Central Valley into productive agriculture use. The Central Valley Project, formed in 1935 to redistribute water from northern California to the Central valley and Southern California helped develop more of the Central Valley. Water for agricultural and municipal purposes was captured in the spring from snow melt in the Sierra Nevada (U.S.) and stored for later irrigation use with an extensive system of dams and canals. The even larger California State Water Project was formed in the 1950s, consisting of the California Aqueduct and its ancillary dams. The California Aqueduct, developed at the cost of several billion dollars, helps store and transport water from the Feather River Basin to agricultural and municipal users statewide. The Colorado River Aqueduct delivers water from the Colorado River to the Imperial Valley of California area and since 1905 the Los Angeles Aqueduct delivers water over from the Owens Valley to the city of Los Angeles. One of the state's most acute problems is its appetite for water. In the extensive fields of the Imperial Valley, irrigation is facilitated in part by the All-American Canal—part of the Colorado River Aqueduct project. Cutbacks in federally funded water projects in the 1970s and 80s led many cities to begin buying water from areas with a surplus; but political problems associated with water distribution continue. Ongoing challenges to develop a long-term plan to end surplus water withdrawals from the Colorado led the federal government to stop the release of surplus river water to the state in 2003.
Agriculture is one of the prominent elements of the state's economy: California leads the nation in the production of fruits, vegetables, wines and nuts. The state's most valuable crops are cannabis, nuts, grapes, cotton, flowers, and oranges. California produces the major share of U.S. domestic wine. Dairy products contribute the single largest share of farm income. California's farms are highly productive as a result of good soil, a long growing season, the use of modern agricultural methods and extensive irrigation. Irrigation is critical since the long dry summers would not allow most crops to grow there--California Indians had almost no agriculture because of this. Extensive and expensive irrigation systems including furrow "gravity" irrigation, sprinkler and drip irrigation systems have been developed to supply the extensive irrigation needs of California. Illegal immigration to the United States has been traditionally drawn to the state, in part, because corporations face intense pressure to control labor costs by using illegal means to harvest California's extensive crops.
Top 30 publicly traded companies in California for 2022according to revenueswith State and U.S. rankings StateCorporationUS 1Apple4 2Alphabet8 3Chevron10 4Meta31 5Wells Fargo47 6Disney48 7Intel62 8HP Inc.63 9TD Synnex64 10Cisco82 11Qualcomm98 12Broadcom123 13Molina126 14Uber127 15Netflix129 16Salesforce133 17Visa137 18PayPal148 19Gilead Sciences150 20Nvidia152 21Amgen154 22Applied Materials155 23AMD167 24PG&E180 25Western Digital221 26Ross223 27Adobe233 28Block234 29Lam Research240 30Edison241Further information:List of California companies Source: Fortune/Patch