A judgment is for the amount the judge said, right?
You get interest too. California law allows you to get 10% simple interest per year on your judgment. California Code of Civil Procedure § 685.010. Simple interest means you don’t get interest on top of your interest (except when you renew your judgment).
What else do you get?
California law allows a judgment creditor to recover “reasonable and necessary costs” (don’t get too excited, these are fairly limited) and also, attorney fees if the underlying judgment provide for an award of contractual attorney fees or where otherwise provided for by law. California Code of Civil Procedure § 685.040. For example, California law allows an employee to recover their attorney fees when they have to hire a lawyer to enforce a wage judgment. California Labor Code § 1194.3.