California Child Support Calculator – Official 2025 Guide

The California Child Support Calculator on this page summarizes how the official California Guideline Child Support Calculator works and what information you need before using it. California law requires courts to follow a statewide uniform guideline when setting child support orders. The guideline is defined in the California Family Code and implemented in the official calculator provided by the California Department of Child Support Services (DCSS).

For a simple step-by-step guide, read our California Child Support Calculator Manual.

Use this article as a manual-style overview before you open the official calculator and enter your own numbers.

Official California Guideline Child Support Calculator

The State of California provides an online calculator that applies the statewide child support guideline in real time:

• California Guideline Child Support Calculator (DCSS):
  
  California Child Support Calculator
  
• Official User Guide (PDF):
  
  Manual – user guide
  
• Instructions inside the calculator:
  use the “Instructions” and help texts in the official DCSS calculator and the User Guide to understand each field before entering your data.

The Payment Estimator (official calculator) applies the statewide guideline to the information you enter in the blank fields. The result is an estimate of the child support amount that may be ordered in your case. A family law judge or child support commissioner has the final authority to set the actual order.

California’s Child Support Guideline Formula

California uses a standard formula in all child support cases, known as the Statewide Uniform Guideline. The core formula is set out in California Family Code section 4055:

CS = K × (HN – (H% × TN))

• CS = child support amount.
• K = the fraction of both parents’ income to be allocated to child support (based on combined income and number of children).
• HN = high earner’s net monthly disposable income.
• H% = percentage of time the high earner has primary physical responsibility for the child (timeshare).
• TN = total net monthly disposable income of both parents.

The calculator does this math for you. Your task as a user is to enter accurate information for income, time share, and relevant deductions so the guideline can be applied correctly.

Information You Need Before Using the Calculator

Before you open the official California Guideline Child Support Calculator, it helps to gather:

1. Each parent’s monthly income

California defines “annual gross income” broadly. It generally includes:

• wages and salary
• self-employment income
• bonuses, commissions, and overtime
• rental income, interest, dividends, and certain benefits

The guideline then applies required deductions (taxes, certain retirement contributions, health insurance, and existing support obligations) to arrive at each parent’s net disposable income. You do not need to calculate all of this by hand: the certified calculators and official DCSS tools help with the tax and deduction components.

2. Percent of time with each parent (timeshare)

Time share is the percentage of time the child spends in the care of each parent, usually measured by overnight stays over the course of a year. For example, a schedule could result in 50/50, 70/30, or 80/20 parenting time.

The percentage assigned to the higher earner (H%) is one of the key inputs in the guideline formula. A small change in timeshare can have a noticeable impact on the estimated support amount, so you should use realistic and current parenting schedules.

3. Mandatory and discretionary “add-ons”

In addition to the basic guideline amount, California law allows for certain add-ons, some mandatory and some discretionary. Typical examples include:

• work-related childcare costs
• reasonable uninsured healthcare expenses for the child
• travel expenses related to visitation when parents live far apart
• educational or other special needs expenses

The official calculator and the court may factor these amounts into the final child support order. You should have estimates or documentation ready for these costs.

How California Courts Use the Guideline

Under the California Family Code, the amount calculated under the statewide uniform guideline is presumed to be the correct amount of child support. However, a judge can deviate from the guideline when the law allows and when following the guideline would be unjust or inappropriate in a particular case.

Examples of situations where a deviation may be considered can include:

• very high income cases where the guideline amount would be more than needed to meet the child’s needs
• special medical, educational, or other needs not fully reflected in the basic formula
• situations where strict application of the formula would not be in the child’s best interests

Any deviation must be supported by written findings that comply with the California Family Code and applicable court rules.

Getting Help With the Calculator and Forms

The official DCSS calculator and user guide are designed for both family law professionals and parents who are not represented by a lawyer. If you need help understanding the calculator or completing the forms, California offers free court-based assistance:

• Family Law Facilitator and Self-Help Center:
  
  Family Law Facilitator – court-based self-help services
  

A family law facilitator can provide:

• information about how to get, change, or enforce child support orders
• help with court forms and paperwork
• referrals to your local child support agency and other services

They do not represent you as your personal attorney, but they can make the process easier to navigate.

Other Useful Official Resources

• California Department of Child Support Services (DCSS):
  
  California Child Support Services – official site
  
• Judicial Council of California:
  
  AB 1058 Child Support Commissioner and Family Law Facilitator Program
  
• Certified guideline support calculators:
  
  Guideline Support Calculators – Judicial Council
  
• Statutory text of the guideline:
  
  California Family Code §4055 – Statewide Uniform Guideline
  

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