What county am I in?

San Francisco, officially the City and County of San Francisco, is a commercial, financial, and cultural center within Northern California. With a population of 808,988 residents as of 2023, San Francisco is the fourth-most populous city in the U.S. state of California behind Los Angeles, San Diego, and San Jose. It covers a land area of 46.9 square miles at the upper end of the San Francisco Peninsula, making it the second-most densely populated major U.S. city behind New York City and the fifth-most densely populated U.S. county, behind four of New York City's boroughs. Among the 92 U.S. cities proper with over 250,000 residents, San Francisco is ranked first by per capita income and sixth by aggregate income as of 2022. San Francisco anchors the 13th most populous metropolitan statistical area in the United States, with almost 4.6 million residents in 2023. The larger San Jose–San Francisco–Oakland combined statistical area, the fifth-largest urban region in the U.S., had a 2023 estimated population of over 9 million.

In the United States, a county or county equivalent is an administrative or political subdivision of a U.S. state or other territories of the United States which consists of a geographic area with specific boundaries and usually some level of governmental authority. The term "county" is used in 48 states, while Louisiana and Alaska have functionally equivalent subdivisions called parishes and boroughs, respectively. Counties and other local governments exist as a matter of U.S. state law, so the specific governmental powers of counties may vary widely between the states, with many providing some level of services to civil townships, municipalities, and unincorporated areas. Certain municipalities are in multiple counties; New York City is uniquely partitioned into five counties, referred to at the city government level as boroughs. Some municipalities have been consolidated with their county government to form consolidated city-counties, or have been legally separated from counties altogether to form independent cities. Conversely, counties in Connecticut and Rhode Island, eight of Massachusetts's 14 counties, and Alaska's Unorganized Borough have no government power, existing only as geographic distinctions.