The California State Board of Equalization offers a sales tax rate chart, as shown on the BOE website, although it does not include every community. A toll-free number is provided for people needing information about a community not listed.
The sales tax rate charts for the state of California are separated by county and city then categorized alphabetically in an online database. A chart is also available in PDF format. A separate link is provided to look up current sales and use tax rates by address. There are other PDF charts that show historical tax rates on the BOE website.