California child support calculator
You can estimate California child support before you talk to a lawyer or go to court, because every case starts from the same formula. Put in each parent's monthly net income and the time the children spend with each of you, and we'll apply the formula in use since September 1, 2024.
$0.00 a month
Put in each parent's net income to see an estimate.
Tell us about your situation and where you are. We'll follow up about the next step.
California's formula starts from each parent's net disposable income, which depends on the tax each parent actually owes. Your result matches the formula for the net incomes you entered, so it's only as accurate as they are. The Department of Child Support Services' free Guideline Calculator works out the taxes too. It's certified by the Judicial Council, and courts must use it in cases a local child support agency handles.
How child support is calculated in California
California's child support guidelines come down to one formula, in Family Code section 4055, and it looks at both parents. Each parent's net disposable income is added together, and a share of that total, called the K-factor, is set aside for the children. How big that share is depends on how much you both earn:
| Both parents' net income a month | Share set aside (K-factor) |
|---|---|
| $0 to $2,900 | 16.5% rising to 20% |
| $2,901 to $5,000 | 19.98% rising to 24.96% |
| $5,001 to $10,000 | 25% |
| $10,001 to $15,000 | 24.99% falling to 19.99% |
| Over $15,000 | Under 20%, falling toward 12% |
The share goes up as the higher earner's time with the children gets closer to half, by up to half again at equal time, and comes back down after that. Support is that share times the difference between the higher earner's net income and their time share of the combined income. If that comes out negative, the lower earner pays instead. For more children, the one-child amount is multiplied by 1.6 for two, 2 for three, 2.3 for four, 2.5 for five, up to 2.86 for ten.
For example, if one parent nets $6,000 a month, the other $4,000, and the higher earner has the child 20% of the time, the higher earner pays $1,200 a month. California changed the table on September 1, 2024, so older calculators and articles often show numbers that no longer apply. Our estimate doesn't include spousal support, hardship deductions, past-due support, different time with different children, or a child with more than two parents.
If the paying parent's net income is under $2,929 a month, full-time statewide minimum wage in 2026, the law presumes they qualify for a low-income adjustment. It can lower support in proportion to how far under that line the parent is, down to nothing for a parent with no income, and the judge picks the amount within that range.
When a judge can order more or less support
A judge treats the formula amount as correct, but can order a different amount when the evidence shows it would be unjust or inappropriate. Some of the reasons a judge weighs:
- An agreement. Parents can agree on a different amount, and the court has to approve it.
- Very high income. When the formula amount would be more than the children need.
- Spending that doesn't match time. A parent isn't paying toward the children's needs in line with their time with them.
- Special circumstances. Different time with different children, equal time with a big difference in the share of income each parent spends on housing, a child's special medical or other needs, or a child with more than two parents.
- The family home. A parent stays in the home while its sale is put off, and it would rent for more than the mortgage, insurance and property tax.
- Earning capacity. What a parent could earn, used instead of what they earn now.
- Hardship. Other children living with a parent, extraordinary health costs or uninsured catastrophic losses can come off that parent's income.
Child care for work or job training and the children's health costs that insurance doesn't cover are added on top of the monthly amount, split by the parents' incomes unless the court sets another split. A judge can also add school or special-needs costs and travel for visits.
Questions parents ask about California child support
How much is child support in California?
For one child, when both parents' combined net income is $5,001 to $10,000 a month and the paying parent has none of the child's time, support is 25% of the paying parent's net income, so $1,500 on $6,000. More time with the paying parent brings it down, and more children raise it. Every case depends on both parents' net incomes and how much time the children spend with each of you.
Does 50/50 custody change child support in California?
Yes. Time is part of the formula, so every percentage point counts. With equal time, the parent who earns more still pays under the formula: with net incomes of $6,000 and $4,000 and a 50/50 schedule, it's $375 a month for one child. When both parents earn the same and split time equally, neither pays guideline support. A judge can adjust when equal time comes with a big difference in the share of income each parent spends on housing.
What is the low-income adjustment in California?
If the paying parent's net income is under $2,929 a month, full-time statewide minimum wage in 2026, the law presumes they qualify for a lower amount. How much lower depends on how far under that line they are. A parent netting $2,500 with one child and no time share owes $487.93 by the formula, and a judge can lower it to as little as $416.47. The other parent can argue that the lowest amount would be unfair, and the judge decides.
Is this the official CA child support calculator?
No. It follows the same formula, starting from the net incomes you enter. Courts use calculators the Judicial Council of California certifies. The Department of Child Support Services' free Guideline Calculator is one of them. It works out each parent's taxes, and courts must use it when a local child support agency handles the case.
Can you change a child support order in California?
Yes. Either parent, or the local child support agency if it handles your case, can ask the court to change it, usually because circumstances have changed, such as income or time with the children. An order doesn't change on its own, including when the formula changed on September 1, 2024. Your court's family law facilitator can help for free.
Where the numbers come from
- California Family Code section 4055, the formula, the K-factor table and the low-income adjustment
- Family Code section 4059, which sets what counts as net disposable income
- Family Code section 4061, which sets how child care and uninsured health costs are split
- The Judicial Council's low-income adjustment thresholds, $2,929 a month for 2026
- The Department of Child Support Services' Guideline Calculator, the state's free certified calculator, which also works out each parent's taxes
Checked September 29, 2026. The low-income threshold changes every January 1.
Talk it through with a California family law attorney
A family law attorney can tell you what a judge is likely to order in your situation, and whether any of these adjustments apply to you.
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