Legal Question in Family Law in California

Support is determined by a computer program based mainly on net income and amount of time the child spends with each parent. If there is only one child of the marriage or relationship each parent is expected to spend 25% of their net income on supporting the child. If one had net income of 1000/mo and the other 2000/mo one is supposed to spend 250 and the other 500. If custodial time is 50/50 then the parent who owes 500 would pay 125/mo., So that 25% of the combined net income is available for the child, pro rata the time the child is in each house. If the parent who has the higer income also had 2/3 of the custodial time, there would be no payment by either parent. If the higher earning parent had 75% of the time, the lower earning parent would actually pay 62.50. These numbers are rough approximations, so don't rely on them to try to calculate support, and figuring out what qualifies as "net income" can be very legally complicated. But that's the basic idea of how it works.