Before using the result
How this child support calculator works
The calculator does only the arithmetic described below. It cannot resolve disputed facts, calculate tax liability, choose a county’s procedure, or predict what a judge will decide. Use it to see how a changed input affects the number and what needs outside help.
Basic support under §4055
CS = K×[HN − (H% × TN)]×Child multiplier
Section 4055 uses both parents’ monthly net disposable income and the higher earner’s approximate share of physical responsibility. The sign of the equation determines who pays basic support. Qualifying child-care and uninsured health costs are additional support under §4062 and appear separately below the basic amount.
Inside the formula
What the four variables mean
| Symbol | Meaning | Value used here |
|---|---|---|
| CS | Child support amount | Monthly basic support before separately calculated add-ons |
| K | Income allocated to support | Current income-band fraction adjusted by the higher earner’s timeshare factor |
| HN | Higher earner’s net disposable income | The larger of the two entered monthly net amounts |
| H% | Higher earner’s approximate physical responsibility | Derived from the percentage entered for parent one |
| TN | Total net disposable income | The sum of both entered monthly net amounts |
The K income bands and low-income rule changed on September 1, 2024. A worksheet built for the earlier law may give a different answer even when the family’s facts are identical.
Child-count multipliers
| Children | Multiplier |
|---|---|
| 1 | 1 |
| 2 | 1.6 |
| 3 | 2 |
| 4 | 2.3 |
| 5 | 2.5 |
| 6 | 2.625 |
| 7 | 2.75 |
| 8 | 2.813 |
| 9 | 2.844 |
| 10 | 2.86 |
Before entering income
Use §4059 net disposable income, not a guessed take-home amount
Gross income
Section 4058 can include wages, bonuses, business profit, benefits, investment income, and other sources before statutory deductions.
Net disposable income
Section 4059 deducts specified items, including actual tax liability, payroll charges, qualifying insurance, ordered support, job expenses, and permitted hardships.
Parenting time
Enter parent one’s approximate share of physical responsibility. If parent two earns more, the calculator converts the percentage to parent two’s H%.
Section 4062 add-ons
Qualifying child care and uninsured health costs are allocated after basic support. This tool cannot determine reimbursement because it does not know who paid the bill.
Worked example
Example: one child, $6,000 and $4,000 net, with 20% higher-earner time
- 1Find TN and HN
Total monthly net disposable income is $10,000. The higher earner’s HN is $6,000.
- 2Identify H%
The higher earner has 20% parenting time, so H% is 0.20.
- 3Calculate K
At $10,000 total monthly net income, the income fraction is 0.25. The 20% timeshare factor is 1.20, producing K of 0.30.
- 4Apply §4055
$6,000 − (0.20 × $10,000) = $4,000. Then 0.30 × $4,000 × the one-child multiplier of 1.00 = $1,200 monthly basic support before add-ons or deviation.
What the result leaves out
Taxes, disputed income, and deviations still need separate work
This tool calculates
- The §4055 income bands
- The higher-earner H% factor
- Multipliers for one through ten children
- The 2026 low-income basic-support range
- Each parent’s share of entered add-ons
This tool does not calculate
- Federal or California tax liability
- Disputed, imputed, or self-employment income
- The §4061(c) same-case spousal-support adjustment
- Hardship deductions or guideline deviations
- Who reimburses whom for an add-on already paid
The 2026 low-income comparison amount is $2,929.33 per month. Falling below it creates a permitted adjustment range, not an automatic zero order. Although the DCSS public calculator remains online, the Judicial Council’s table currently lists it as decertified and not recertified for 2026–27. For a court-use calculation, ask the family law facilitator or use software on the current certified list.
See the Judicial Council’s certified-calculator list ↗What to gather
Use records, not memory, for the support inputs
- Federal and California returns, W-2s, 1099s, pay statements, and benefit records for both parents.
- The tax calculation and records supporting each deduction claimed under §4059.
- Business, rental, investment, bonus, commission, and recurring overtime records.
- A parenting calendar showing actual responsibility instead of only a label such as “joint custody.”
- Invoices and proof of payment for work-related child care and uninsured child health costs.
- A calculation from the family law facilitator or currently certified software before presenting a number in court.
Court and filing details for Riverside County
The §4055 equation is statewide; Riverside County controls the filing details
The calculator uses the same California Family Code equation regardless of county. Riverside County still determines where papers go, which local rules and e-filing instructions apply, how a fee waiver is handled, and where a self-represented parent can ask for procedural help. Those local details do not change the math, but they can change what must accompany a filing.
Riverside's 2026 fee schedule lists $450 for a divorce petition or a respondent's first paper. The extra $15 reflects the county's courthouse-construction surcharge after the statewide offset. Use the court's address and venue tools before filing.
Family-law court
Riverside Superior Court Family Law Division
Listed court location or service area: Riverside / Blythe / Indio / MenifeeFirst-paper fees
$450 for the petition; $450 for the response
Fee source checked August 12, 2026.Later request or motion
$60 is the listed motion fee
Service, copies, and other filing charges may be additional.Support calculation for court
Use currently certified software or the family law facilitator.
The Judicial Council currently lists the public DCSS calculator as decertified.What to verify before taking a number to court
Parenting-time percentages, tax treatment, hardship deductions, and add-on expenses can be disputed even when both sides agree on the formula. The on-screen estimate helps identify those inputs; it is not a filing attachment or a substitute for a calculation accepted by the court.
- Use the court’s address or venue instructions to confirm the correct Riverside County filing location.
- Check local rules and e-filing requirements before submitting support declarations or exhibits.
- Separate basic support from child-care and uninsured-health add-ons when comparing results.
- Ask the facilitator or certified-software provider which printout and income records the court expects.
Common questions
What California law says about this calculation
How is child support calculated in California?
For one child, California starts with CS = K[HN − (H%)(TN)]. The formula uses both parents' monthly net disposable income and the higher earner's approximate share of physical responsibility. A statutory multiplier applies when the order covers two through ten children.
Did California change its child support formula?
Yes. New income bands and a revised low-income adjustment took effect September 1, 2024. A worksheet built for the earlier formula may not match a calculation under the law now in force.
What is the California low-income threshold in 2026?
The comparison is $2,929.33 a month: $16.90 an hour for 40 hours a week, annualized and divided by 12. If the paying parent's monthly net disposable income is below that amount, the law presumes an adjustment should be considered. It does not automatically reduce support to zero.
Why does this calculator ask for net disposable income?
Section 4055 needs the monthly net disposable income defined by §4059. That figure deducts actual tax liability and only the items the statute permits, so ordinary paycheck take-home pay can be the wrong input.
Are child-care and medical expenses part of basic support?
Usually not. Qualifying child care actually incurred for work or job training and reasonable uninsured health costs are additional support under §4062, unless child care was specifically included in the guideline calculation. Education, special-needs, and visitation-travel costs may also be ordered. The court calculates basic support first and allocates add-ons afterward.
Is this a Judicial Council-certified calculation?
No. This site applies the statutory equation to net-income figures supplied by the user; it does not calculate taxes and is not certified for court use. The Judicial Council currently lists the DCSS public calculator as decertified and not recertified for 2026–27. For a court-ready calculation, use software on the current certified list or ask the local family law facilitator.
Read the law and court instructions
Sources for the rules on this page
- California Family Code §4055 — statewide child support formula
Section 4055 contains CS = K[HN − (H%)(TN)], the income bands in use since September 1, 2024, the child-count multipliers, payment direction, timeshare averaging, and the low-income adjustment.
- California Family Code §§4058–4059 — income
Sections 4058 and 4059 define gross income and the deductions used to reach net disposable income, including actual tax liability, payroll taxes, qualifying insurance, other ordered support, job expenses, and hardships.
- California Family Code §4061 — allocation of child support add-ons
Section 4061 calculates basic support first, then allocates qualifying add-ons using adjusted net incomes. It reduces the paying parent's net by basic support but does not add that payment to the receiving parent's net.
- California Family Code §4062 — child support add-ons
Section 4062 treats qualifying child care and reasonable uninsured health costs as additional support, with education, special-needs, and parenting-time travel costs left to the court's discretion. Child care already included in the guideline is not added twice.
- California Child Support Services — public guideline calculator notice
The DCSS public calculator remains online and describes its result as an estimate. Its availability does not establish certification; the Judicial Council's current status table controls that question.
- Judicial Council — status of guideline support calculators
The Judicial Council's status table lists the DCSS public calculator as decertified and identifies the programs currently certified for California court proceedings.
- California Rule of Court 5.275 — certified support software
Rule 5.275 sets certification standards for support software and explains when another certified program may be used while the DCSS calculator is decertified or unavailable.
- California DIR — 2026 minimum wage
The statewide minimum wage is $16.90 an hour beginning January 1, 2026. Full-time monthly earnings at that rate supply the low-income comparison in §4055.
- Riverside Superior Court Family Law Division
Family-law filing locations, local procedures, and court services for Riverside County.