The purpose of child support is to help a parent adjust to supporting his or her children on a single income. California courts have a complex formula to determine the child support amount and the outcome will differ from case to case. More often than not, the parent with the higher income will have to pay child support to the lower-earning parent.
Of course, this situation can change based on the amount of time each parent spends taking care of the children. If the higher-earning parent is also the custodial parent, the amount that he or she will pay to the lower-income parent will be much less than if the lower-income parent had custody.