California Divorce Calculator
Divorce in California turns on the monthly number that goes to the children, and California does not leave it to guesswork. Family Code section 4055 sets one statewide formula for guideline child support, built on each parent’s net disposable income, the higher earner’s timeshare and a statutory K factor. This calculator now runs that actual formula.
Enter both parents’ gross incomes, filing statuses and section 4059 deductions, and the tool works out each net income, applies CS = K [HN – (H%)(TN)] with the current K table and multiplier, then checks the low-income adjustment in section 4055(b)(7). Spousal support gets no number here: California has no statewide formula for it.
This runs the real section 4055 guideline formula on section 4059 net incomes. Taxes behind those incomes are approximated: the method and its limits are stated in the tax section below. Not a court order or legal advice.
Quick Answer
Key takeaways
- Child support is the section 4055 formula on net disposable income, not a percentage of gross pay.
- K comes from a statutory table based on combined net income and timeshare.
- Below $2,929 a month of payer net income in 2026, the low-income adjustment can cut the amount.
- There is no statewide spousal support formula, so this tool prints no invented percentage for it.
- Quick Answer
- How to use this California guideline child support calculator
- The section 4055 formula, step by step
- How the taxes behind net income are approximated here
- Worked example: $8,000 and $3,000 gross incomes, two children, 20% timeshare
- The low-income adjustment in section 4055(b)(7)
- What a court adds and decides beyond this number
- What competing calculators miss, and what this one does differently
- Frequently Asked Questions
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How to use this California guideline child support calculator
Fill in one block per parent. Gross income means income from every source under Family Code section 4058: wages, commissions, bonuses, rents, pensions and benefits. Pick each parent's real filing status: the taxes behind net income depend on it. Add the section 4059 deductions: mandatory dues and retirement, health premiums, support paid for a different case. Spousal support received from a different case counts as income; child support received for other children does not.
Finish with the number of children and the higher earner's timeshare. The results box shows the amount, who pays whom, both net incomes, TN, the K factor, the multiplier, and the amount before and after any low-income adjustment. Pre-filled values are the worked example below.
The section 4055 formula, step by step
California's guideline is one algebraic formula, and courts must use it unless a statutory reason to depart is stated on the record.
CS is monthly child support. HN is the higher earner's net monthly disposable income. TN is both net incomes added together. H% is the higher earner's approximate timeshare. K comes from the table below.
Gross to net. Annual gross minus the section 4059 deductions, divided by 12.
Find the K fraction. Combined net income (TN) selects a row of the K table in section 4055(b)(3).
Apply timeshare. Multiply by (1 + H%) at 50% or less, or (2 - H%) above 50%. That gives K.
Run the formula, then multiply for children by the section 4055(b)(4) factor: 1.6 for two, 2 for three, 2.86 for ten.
Check the low-income adjustment in section 4055(b)(7), described below.
| Total net disposable income per month (TN) | K fraction in section 4055(b)(3) |
|---|---|
| $0 to $2,900 | 0.165 + TN/82,857 |
| $2,901 to $5,000 | 0.131 + TN/42,149 |
| $5,001 to $10,000 | 0.250 |
| $10,001 to $15,000 | 0.10 + 1,499/TN |
| Over $15,000 | 0.12 + 1,200/TN |
These bands apply since September 1, 2024 under SB 343; older tables online are repealed. The statute's own example checks row one: at TN of $1,000 and a 20% timeshare, K = (1 + 0.20) x (0.165 + 1,000/82,857) = 0.21. A positive result is paid by the higher earner; a negative result means the lower earner pays the absolute value, per section 4055(b)(5).
How the taxes behind net income are approximated here
Section 4059(a) requires each parent's actual tax liability. This calculator estimates it one stated way: annualise gross income, subtract the 2025 standard deduction ($15,750 single or married filing separately, $23,625 head of household), apply the 2025 federal brackets, then the 2025 California brackets after the California standard deduction ($5,363, or $10,726 head of household) and $149 exemption credit. Then deduct FICA (6.2% Social Security to the $176,100 wage base, plus 1.45% Medicare), SDI at 1.2%, and your entered deductions.
Worked example: $8,000 and $3,000 gross incomes, two children, 20% timeshare
The calculator is pre-filled with this case. Parent A earns $8,000 a month, files single, with $100 of mandatory deductions and $250 of health premiums. On $96,000 a year: $1,047 federal and $402 California tax a month, plus $612 FICA and $96 SDI, leaving net disposable income of $5,492. Parent B earns $3,000, files head of household, pays $150 of premiums: $103 federal and $12 California tax, $230 FICA and $36 SDI leave $2,470.
Combined net income of $7,962 sits in the $5,001 to $10,000 band, so the K fraction is 0.250 and K = (1 + 0.20) x 0.250 = 0.300. Inside the brackets: $5,492 - (0.20 x $7,962) = $3,900. Times K gives $1,170; times the 1.6 multiplier gives $1,872 a month, paid by Parent A to Parent B. Parent A is well above the $2,929 low-income threshold, so no adjustment applies.
After the order, both households rebuild a budget around the payment. The bills to income ratio calculator shows what share of take-home pay new commitments consume, and the adjusted income calculator frames what is left.
The low-income adjustment in section 4055(b)(7)
When the paying parent's net income is below monthly gross pay from full-time work at the minimum wage, the law presumes a reduction. For 2026 the wage is $16.90 an hour, so the threshold is $2,929 a month (Judicial Council). The maximum reduction is the guideline amount multiplied by (threshold minus the payer's net income), divided by the threshold. This calculator applies that maximum, shown as its own line; $0 means the check ran and did not apply. The presumption is rebuttable and a court may apply less, so a court figure here can be higher, never lower on this point.
What a court adds and decides beyond this number
The guideline amount is the start of a real order, not the whole order. Courts add mandatory add-ons under section 4062, chiefly work-related childcare and uninsured medical costs, shared in proportion to net incomes since September 2024. A court can also grant hardship deductions (sections 4070 to 4073) and depart from the guideline only for section 4057 reasons stated on the record.
Spousal support sits outside the formula. Temporary support follows local formulas that vary by county; long-term support is set under Family Code section 4320: needs, earning capacity, the marital standard of living, assets, health, age, and self-support, generally within half the length of a marriage under 10 years. Property is a third track: under section 760, marital assets and debts are presumed community property and usually divided equally; this calculator does not divide property. The affordability ratio calculator helps check new housing costs against the final order.
What competing calculators miss, and what this one does differently
Miss 1: the pre-2024 K table. The K bands changed on September 1, 2024. Tools still running the old bands compute a repealed guideline. This page prints the current table in full.
Miss 2: one total, no working. Most tools hide the net incomes, K factor and multiplier behind one number. Here each is its own results line, as a court states them under section 4056.
Miss 3: the low-income adjustment described but never computed. Competitors mention section 4055(b)(7) in FAQs and ignore it in the math. This calculator tests the payer against the $2,929 threshold on every run.
Miss 4: invented spousal percentages. A flat percentage of the income gap appears in no California statute. This page explains the section 4320 process instead.
Frequently Asked Questions
It runs the actual section 4055 formula, with the current K table, multi-child multipliers and low-income adjustment, on net incomes under section 4059. It is not certified software: taxes are estimated with the stated 2025 bracket method, without credits, so the official DCSS calculator can differ. Treat it as a formula-true estimate, not a court figure.
For each parent it annualises gross income, estimates federal and California tax from the 2025 brackets and standard deductions for the filing status picked (California also gets the $149 personal exemption credit), then deducts FICA, California SDI at 1.2%, and your mandatory deductions, health premiums and support paid. Divided by 12, that is monthly net disposable income, per sections 4059 and 4060.
K is the share of combined net income section 4055 allocates to child support. Its fraction comes from the statutory band table printed on this page, and it is multiplied by (1 + H%) at a timeshare of 50% or less, or (2 - H%) above 50%. The current bands apply since September 1, 2024; older tables online are repealed.
Section 4055(b)(7) presumes a reduction when the payer's net income is below monthly full-time minimum-wage pay: $2,929 in 2026. The maximum reduction is the guideline amount multiplied by (threshold minus net income) divided by the threshold. This calculator applies that maximum, shown as its own line. A court can apply less or refuse it, so a court figure here may be higher.
Because California has no statewide spousal support formula. The earlier version of this page printed a flat percentage of the income gap; no statute contains that figure. Temporary spousal support follows local formulas that vary by county, and long-term support is set by a judge weighing the section 4320 factors. The tool now calculates the one support figure California law sets by formula: guideline child support.
Mandatory add-ons under section 4062, such as work-related childcare and uninsured medical costs, added by a court on top of guideline support. It also leaves out tax credits, hardship deductions (sections 4070 to 4073), deviations (section 4057), property division, debts and attorney fees.
Use it as an informed estimate, not as the order. The formula is the real one, but the tax step is approximated and a court also weighs disputed income, hardship and add-ons. Before agreeing to a figure, run the official DCSS calculator or take your Income and Expense Declaration to an attorney or court self-help center.
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References
- California Family Code section 4055, "Statewide uniform guideline": formula, K table, multipliers. California Legislative Information: Family Code 4055. Accessed October 2026.
- California Family Code section 4058, "Annual gross income": what counts, and excluded child support received. California Legislative Information: Family Code 4058. Accessed October 2026.
- California Family Code section 4059, "Computing annual net disposable income": tax and deduction rules. California Legislative Information: Family Code 4059. Accessed October 2026.
- California Family Code section 4320, "Circumstances to consider in ordering spousal support". California Legislative Information: Family Code 4320. Accessed October 2026.
- California Family Code section 760, "Community property presumption". California Legislative Information: Family Code 760. Accessed October 2026.
- Judicial Council of California, "Guideline Support Calculators": certified calculators and the 2026 low-income threshold, $2,929. California Courts: Guideline Support Calculators. Accessed October 2026.
- California Department of Child Support Services, "Guideline Calculator": the official free calculator. California DCSS: Guideline Calculator. Accessed October 2026.
- California Courts Self-Help, "Child Support": how cases work and getting help without a lawyer. California Courts Self-Help: Child Support. Accessed October 2026.