Splitting up, whether through a divorce or a more informal situation, is complex when you have children with someone. One of your first questions may be, “How is child support calculated in California?” If you go to court and have your child support assigned to you by a judge, your amount could differ, depending on how the judge looks at your situation. Under California law, the judge can weigh other factors besides the numbers in the formula.

While a skilled attorney can accompany you in court and advocate for the results you seek from your child support case, it is better to decide on an amount outside of court that works for both parties. Deciding on an amount outside the court can lead to a more amicable relationship between both parents, fostering cooperation.

How is child support calculated in California?

What Goes Into the Child Support Formula?

While both parents’ incomes are necessary, California’s guidelines give weight to the information of the higher-earning parent. These guidelines include values like disposable income and time spent with the child.

While child support payments should not be the primary factor in deciding your time with your children, more time spent with them can lead to a lower child support payment and vice versa. Although this is different in other states, it is essential to understand that the parents’ combined income is not the only factor contributing to the child support formula in California.

The more significant the gap between the parents’ income and the less time the higher-earning individual spends with the child, the higher the child support amount will be.

The Child Support Formula

The formula that California uses to calculate child support is just a guideline. Although it can estimate how much child support you can expect to pay or receive, it is not exact. If you are dealing with a child support case, speak with your lawyer or someone in the legal system before you make any decisions based on the number that the formula gives you.

The equation used is CS = K (HN – (H%) (TN)).

Descriptions of the letters are below:


As expected, CS is the child support amount we are looking for. We receive the child support estimate after plugging known information into the formula. Note that this value changes when you have multiple children.


K is both parents’ income devoted to child support. Income is sometimes thought of as gross or net, with or without tax. In this case, though, it is gross income without tax taken out. K’s calculation comes from a formula that considers non-monetary values, such as how much time the highest-earning parent spends with the child.


This value, HN, is the higher-earning parent’s monthly net disposable income.


Here, we input the percentage of time that the higher earner will have primary responsibility for the child or children compared to the other parent. When parents spend various amounts of time with different children, H%’s calculation rests on the average of each percentage for all children.


TN, or total net, is both parents’ combined monthly net disposable income.

Using the Formula

Although the formula may seem straightforward, there are specific factors and situations where it helps and others where it may need to be more accurate. Typically, courts use the formula as a baseline for situations involving divorces, unmarried parents, domestic partnerships, or modifications of existing support orders.

When gathering information to put into the formula, there are a few things to remember.


You will need each parent’s net disposable and gross income. Both numbers are vital information in determining a more accurate answer. Gross income includes:

  • Wages
  • Salaries
  • Self-employment income
  • Investment income
  • Workers’ compensation payments
  • Pensions
  • Any other sources of income

Many of these amounts may require help to calculate. An experienced child support law office will have staff who can assist you in finding the correct numbers.

Time Spent

The time spent with a child should be a percentage value, but this may not be easy to calculate in some less formal arrangements. Developing a formal parenting plan or agreement to lay out the routine that your child will follow is wise. When attempting to find a parent’s percentage of time spent, you will have the agreement to look at and find a more straightforward answer.

Contact a child support lawyer if you need assistance drafting a parenting plan or agreement. They may have templates or guidelines for you to start with.


Q: What Is the Formula for Calculating Child Support in California?

A: The formula for calculating child support in California is complex and requires precise information. Even when you use the formula correctly, your result might be different from the result you receive after a child support case. A child support attorney can give you an accurate estimate based on your circumstances.

The formula is CS = K (HN – (H%) (TN)), where:

  • CS is the child support amount and answer to the formula.
  • K is the total income that both parents must devote to child support.
  • HN is the higher-earning parent’s monthly net disposable income.
  • H% is the percentage of time that the higher earner will have primary responsibility for the child or children.
  • TN is both parents’ combined monthly net disposable income.

Q: What Is the Average Child Support Payment per Child in California?

A: The average child support payment per child in California can vary depending on the income bracket and other factors of the household a child lives in. The exact amount that a parent will end up paying per child hinges on many factors, such as time spent with the child, the child’s maintained lifestyle, and the income of both parents.

Q: Is California Child Support Based on Gross or Net Income?

A: California child support is calculated based on the higher-earning parent’s net income, the parents’ total combined income, the time spent with the child, and other relevant factors. While some numbers in the formula are net income, some are gross income. Overall, the formula gives an estimate of child support, not the exact number that you would get from a judge.

Q: How Much Is Child Support in California When You Have 50/50 Custody?

A: Child support when you have 50/50 custody in California depends on how much income you and your co-parent make. While the amount of child support changes with custody type, the amount does not necessarily go to zero. When you have 50/50 custody or equal joint physical custody, your child support amount is less than it would be if the higher-earner had no custody.

Get Help With the Law Offices of Schwartz & Godbey

Thinking about divorce is complicated when you have children. You want what’s right for your child. At the Law Offices of Schwartz & Godbey, we can help ensure that you meet your child’s financial needs in a way that makes sense for everyone involved. Schedule a consultation today to gain insight into what your child support amount might be going forward.