WEBSan Joaquin County (/ ˌ s æ n hw ɑː ˈ k iː n / ⓘ; Spanish: San Joaquín, meaning "St. Joachim"), officially the County of San Joaquin, is a county located in the U.S. state of California. As of the 2020 census, the population was 779,233. [7] The county seat is …