Alameda County is on the eastern side of San Francisco Bay. Oakland is its county seat, and other communities include Berkeley, Fremont, Hayward, and Livermore.
Alameda County facts
County estimates: American Community Survey (ACS) 2020–2024 5-year release. Boundary and land area: U.S. Census Bureau TIGERweb. Data may change as sources are updated.
Interactive Alameda County map
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Map tiles © OpenStreetMap contributors. Map boundaries are not legal property lines. Scroll-wheel zoom is disabled to make page scrolling easier.
Where is Alameda County?
Alameda County is on the eastern side of San Francisco Bay. Oakland is its county seat, and other communities include Berkeley, Fremont, Hayward, and Livermore.
The county stretches from bayside urban communities into inland valleys and hills. It forms part of the wider Bay Area, but county estimates and government boundaries should not be confused with the entire region or with one city.
Berkeley, Oakland, and Fremont are often discussed together as East Bay communities, yet their housing markets and city services can differ. Countywide American Community Survey figures provide a standardized comparison rather than a neighborhood-level description.
Alameda County FIPS code and county seat
Alameda County’s five-digit FIPS code is 06001. Its first two digits, 06, identify California; the last three digits, 001, identify the county. The full five-digit code should be retained when joining public geographic datasets.
Oakland is the county seat. The county seat is the administrative center for county government. It does not necessarily represent the largest city or the location of every service. County FIPS identifiers should not be confused with ZIP Codes, city boundaries, or school districts.
Population, household income, and housing estimates
Population, median household income, median home value, median age, and poverty data on this page are drawn from the 2020–2024 American Community Survey (ACS) five-year release. These are estimates, with sampling error, rather than a real-time census. Household income and owner-occupied home value use the inflation-adjusted dollar basis of the ACS release. A countywide median is not a quote for an individual household or property.
County boundary and land-area data use the Census Bureau’s TIGERweb geography layer. Population density is calculated from the ACS population estimate and mapped land area. Geographic boundaries may have a different vintage from demographic data, so small differences between data sources are possible. Land-area figures exclude water area.
How to use the interactive county map
Use the interactive map above to inspect the county’s outline. Drag to pan and use the zoom buttons to explore the boundary in its wider region. The map is a general geographic reference: it is not a legal survey, tax-parcel map, flood map, election precinct map, or emergency-service boundary. Consult the relevant government authority before making jurisdictional decisions.
If the county boundary service cannot load, the map area displays a status message. The county seat and FIPS code remain visible without the external services.
Compare Alameda County with other California counties
You can explore Santa Clara County and San Francisco County, or use the side-by-side county comparison tool to select two counties and compare income, population, housing, and density. Differences in medians and area do not by themselves establish which county is better for every household or business.
Frequently asked questions
Is Berkeley in Alameda County?
Yes. Berkeley is one of the cities in Alameda County. Oakland is the county seat, and both cities are part of the East Bay.
What is the county FIPS code for Alameda County?
The five-digit code is 06001. You can search it with our County FIPS Code Lookup tool. Leading zeros, when present, are part of the identifier.
Why might the county population or map show unavailable?
The statistics and map load from external Census-related services. If the services fail or load slowly, the page shows an unavailable or retry message rather than an invented value. For more detail, visit Data and Methodology.
Sources and related county tools
Sources: U.S. Census Bureau ACS, Census TIGERweb, and Census QuickFacts. You can also explore the California county directory, ZIP Code to County Finder, and What County Am I In? tool.