Selling a rental home in California - how are capital gains taxed? Federal or State? Both?

I need help.  I am selling a rental home I own in California (I currently live out of state).  I don't meet any of the requirements to waive capital gains taxes on the sale.  How does capital gains taxes work though, I've read everywhere that it's 15%, but is that just the federal govt's portion?  Is there an additional capital gains tax that I'll owe the state of California?  And if so approx what % is the state capital gains tax?