California Child Support Calculator

You're sitting down to create a post-divorce monthly budget. How much should you include in child support? 

California officials created a calculator to help you answer that crucial question. The tool gives estimates only, so your payment could be larger or smaller than the total you see on your computer screen. 

But this tool can give you a good idea of how much you should include in your monthly budget so you can support your child per California law. If you're hoping to agree with your spouse and stay out of court, this tool could be a big help. Just know that you’ll have to refine the total further beyond the estimate given.

Hello Divorce's free online California Child Support Calculator

We've provided information about the State of California's Child Support Calculator below, but we created our own estimator that is more user-friendly and often more accurate. Our free tool provides a quick, accurate estimate of your child support payments, letting you save or update your information in real-time. Plus, it doesn't time out like the State calculator does after 30 minutes of inactivity.

We designed our free estimator to be the most user-friendly child support calculator on the web. Simply input information on your income(s), tax bracket, and timeshares with your kids. We guide you through, so if you forget a document, no worries. Try our California Child Support Estimator now to get a good idea about how much child support you'll be paying or owed.

Use our free CA Child Support Estimator

The California Child Support Services Calculator 

Parents are required to offer financial support until a child is 18 years old (sometimes even longer). If couples divorce, a non-custodial parent (who doesn't live with the child nor provides day-to-day financial assistance with food, housing, and other expenses.) pays the other parent child support. 

The California Child Support Services Calculator is free. Anyone can use it to get an estimate of how much they might pay each month in child support. 

To use the tool, parents need a great deal of information from both parties, including these items:

  • Recent tax returns
  • Paycheck stubs
  • W2s or 1099s
  • Disability or unemployment benefits documents
  • Bills related to child care and health insurance
  • Mandatory retirement contributions
  • Bills or expenses related to jobs (that aren’t covered by employers)
  • Spousal support bills or child support bills stemming from other relationships 
  • Health care expenses 

A friendly warning: The calculator has a 30-minute timeout feature. If you’re using the tool and need to step away to find a receipt or have another interruption, you could lose your place. Starting over can be incredibly frustrating. Preparation is critical, so the process is efficient. Have all the paperwork listed above ready, and allow yourself an hour to be sure you can complete it all in one round. 

What factors does the calculator examine?

Child support estimators use plenty of financial factors to determine a child support estimate. All of these data points indicate how much a parent can put toward a child's welfare and how much help the custodial parent will need to keep the child safe, healthy, and secure. 

These are the factors included within the tool


Parents include information about the children they have in common due to their marriage, and they identify how many are younger than 18. Parents also indicate how much time the children typically spend with each parent. 


Parents enter data about both federal and California taxes, including these things:

  • Their status when they filed
  • How much they made 
  • How much they claimed for children 

Wages and salary 

Parents identify how much they made from employers or self-employment gigs. If they're claiming unemployment or disability, they can enter the data too. Parents with new spouses also need to include information about wages and salary for that person. 

Monthly deductions

This portion of the form can be a little confusing, especially if you don't pay some of these fees each month. These are the data points included:

  • Child support 
  • Spousal support 
  • Property taxes
  • Mortgage interest
  • Union dues 
  • Health insurance premiums
  • Job-related expenses

Other children 

Some parents live with children from other relationships. If this is the case with you or your ex, you will fill out data about those children and their expenses. A calculator is embedded within the tool to make this easier. 

Monthly child support add-on

Some parents pay a little extra each month for their children to cover childcare, school fees, and travel for visits. Those expenses can be included within the tool. 

Other add-ons

This section of the tool includes data points that don't fit anywhere else, such as temporary spousal support

Can you change a child support order?

Parents are legally required to support their children. California courts can make rulings about how much one parent should pay the other, and those rules are binding. But family circumstances can change, and when they do, the child support order should shift, too. There are steps you can take to have it adjusted. 

If a judge makes a child support order, one or both parents must prove that there has been a change in circumstances since that order. Parents could prove any of the following:

  • Changing income
  • Loss of a job
  • Incarceration
  • Changes in child custody
  • Differences in child support required (such as a child aging out of childcare)

These all can impact the child support order. The process requires many forms and a step-by-step process. Follow the necessary steps carefully to ensure no delays.

Fill out paperwork

Start with two forms that signal you'd like a change in child support:

  • Request for Order (FL-300)
  • Income and Expense Declaration (FL-150)

Make two copies of these documents. 

File your paperwork

Go to the courthouse in your county with the original and your copies. You may need to pay a filing fee, depending on who is involved in your case. The clerk will stamp all of your papers and write a court date on the form FL-300.

Serve your spouse

Have someone who is 18 or older and not associated with the case serve your spouse one copy of the stamped papers, along with two blank forms:

  • Responsive Declaration to Request for Order (FL-320)
  • Income and Expense Declaration (FL-150)

Give your server a Proof of Personal Service (FL-330) form. Ask your server to fill it out and give it back to you. 

File your proof

Go back to the courthouse with the FL-330 form all filled out. 

Go to your hearing 

The court assigned a date for your hearing, and you must appear. Bring all of your papers and your proof with you to the hearing. 

Get help

Your county's Family Law Facilitator or local child support agency can review your case for free. The local child support agency can even grant a modification without a court case. If you think heading back to court is too difficult, ask for help with this process



Calculate Child Support. California Child Support Services. 
Guideline Calculator. California Child Support Services. 
California Guideline Child Support Calculator User Guide. (April 2021). California Child Support Services. 
Changing a Child Support Order. Judicial Branch of California. 
Changing a Child Support Amount. California Child Support Services.
Divorce Specialists
After spending years in toxic and broken family law courts, and seeing that no one wins when “lawyer up,” we knew there was an opportunity to do and be better. We created Hello Divorce to the divorce process easier, affordable, and completely online. Our guiding principles are to make sure both spouses feel heard, supported, and set up for success as they move into their next chapter in life.