California Child Support Estimator

Enter each parent’s net monthly income, tweak the parenting-time percentage, and add health-care or child-care costs to see an instant, guideline-style estimate. This free tool mirrors the statutory formula (Cal. Fam. Code §4055) so you can negotiate or budget with confidence—no DissoMaster® subscription required.

Parents calculating child support payments at a kitchen table

Calculate California Child Support Online

Move the sliders or type numbers directly—results update automatically.

10 000
5 000
50 %
0
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0

Estimated Guideline Support

$0 / month

  • Base support: $0
  • Add-ons share: $0
  • Total: $0

Estimator applies Cal. Fam. Code §4055 math but is not certified DissoMaster® software. Courts may deviate based on documented evidence.

How Much Child Support with 70/30 Custody?

Scenario Income Split (A/B) Custody % (A/B) Add-Ons Estimated Support
Example 1$6 000 / $3 00070 / 30$0$840
Example 2$8 000 / $4 00070 / 30$300 health$1 120
Example 3$10 000 / $2 50060 / 40$600 child-care$1 375
Example 4$5 000 / $5 00050 / 50$0$0
Example 5$12 000 / $3 00080 / 20$250 other$1 920

Notice how a 10 % custody swing changes support by several hundred dollars at the $8 000 / $4 000 income level—highlighting why accurate parenting-time tracking matters. Use our parenting-plan template to document timeshare precisely.

How to Read Your Estimate

  • Line A – Net income: Start with take-home pay after mandatory deductions. Overtime counts unless rare and unpredictable.
  • Line B – Parenting-time percentage: Judges rely on overnights. Track exchanges in a shared calendar.
  • Line C – Base support: Formula shifts money from the higher-earning parent to equalise household standards.
  • Line D – Mandatory add-ons: Health-insurance premiums and child-care costs are split pro-rata. See our financial-disclosures guide for evidence requirements.
  • Line E – Discretionary add-ons: Unreimbursed medical or private-school tuition may be added by court order.
  • Line F – Final guideline: Result is presumed correct but can be adjusted for proven hardship—learn how in our modification guide.

Free DissoMaster Alternative

This estimator uses the same math engine but skips advanced tax-credit tweaks. Expect a ±5 % variance from certified software. For courtroom filings, attach a printed guideline from your county facilitator or licensed program.

Disclaimer: This calculator is for educational purposes only. It does not create an attorney-client relationship and should not be submitted as evidence. Always verify numbers with official guideline software or legal counsel before filing.

Frequently Asked Questions

Not necessarily. Guideline support balances both income and parenting-time. When parents earn similar amounts, a true 50/50 split can yield zero or very low support. But if one parent earns substantially more, the court may still order payments to keep the child’s living standard consistent across homes. Test your own numbers above or read our joint custody guide.

You may file a Request for Order (FL-300) seeking modification. Courts look for a material change—commonly a 10 %+ swing in income or a shift in custody time. Gather new pay stubs, complete a fresh FL-150, and serve the other parent. Our step-by-step modification guide explains timelines and filing fees.

For most wage-earner scenarios, results land within a few percentage points. The biggest differences arise when parents have complex tax deductions, self-employment income, or multiple children across cases. Think of this as a planning tool—reliable enough for mediation or budget prep, but verify with certified software before submitting to the judge.

Courts generally require a guideline printout from approved software (e.g., DissoMaster, XSpouse) or the county’s facilitator. You may, however, attach your own calculations as a demonstrative exhibit to support negotiation. For official hearings, bring the certified guideline and an updated income & expense declaration.

California can deviate from the strict formula where one parent’s income greatly exceeds the child’s reasonable needs. Judges may cap support or use a reasonable needs test in high-income cases. If monthly guideline exceeds your child’s actual expenses, be prepared with budgets and expert testimony. See our forthcoming enforcement & deviation guide.

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