Percentage of income child support calculator

Used by six states. Applies a fixed percentage to the non-custodial parent's income based on the number of children.

StateUses Percentage of Income model

Texas caps at 40% of net resources.

Your state determines which calculation model applies.

Parent A monthly gross income

Parent B monthly gross income

Enter gross (before tax) monthly income for both parents. Include wages, salary, overtime, self-employment income, and regular bonuses.

Number of childrenParent A parenting time20%

Parent B: 80%

The percentage of overnights Parent A has per year. 50% = equal parenting time.

Estimated monthly child support

$750/month

Based on Texas's Percentage of Income guidelines

Based on income and parenting time, Parent A would likely pay Parent B approximately $750 per month.

Calculation breakdown

Non-custodial parent income$3,750
Guideline percentage20%
Base obligation$750
Add-ons+ $0
Final obligation$750

Annual support

$9,000

12-year projection (to age 18)

$108,000

Has your income changed significantly since your last order? You may qualify for a modification. See modification calculator →

This calculator provides estimates based on simplified state guideline formulas and does not account for all factors a court may consider. Actual orders depend on judicial discretion, income verification, imputed income, and case-specific factors no calculator can capture. This is not legal advice. Consult a licensed family law attorney in your state. Read full disclaimer.

How percentage of income works

In percentage states, only the non-custodial parent's income is used in the base calculation. A fixed percentage from a state-published table is applied based on the number of children. Add-ons may be split separately depending on the state.

State percentage tables

State	1 child	2	3	4	5+	Income basis
Illinois	20%	28%	32%	40%	45%	Gross
Mississippi	14%	20%	22%	24%	26%	Gross
Nevada	18%	25%	29%	31%	33%	Gross
North Dakota	14.35%	20.35%	22.35%	24.35%	26.35%	Net
Texas	20%	25%	30%	35%	40%	Net
Wisconsin	17%	25%	29%	31%	34%	Gross

Texas net resources

Texas applies its percentage to net resources: gross income minus federal income tax for a single person claiming one personal exemption, Social Security taxes, state income tax, union dues, and the cost of health insurance for the children. For most wage earners, net resources approximate 75% of gross.