Where a child support figure actually comes from

Published 2026-11-06 · Last reviewed 2026-11-06

There is no national child support formula. There is a federal requirement that every state publish one, and then there are fourteen different answers to the same question - so a calculator that asks for an income and prints a number without naming whose table it used is printing a guess with a decimal point on it. This guide is about the part that decides the answer: which figure the state multiplies, what it multiplies it by, and which lines the family, rather than the table, has to fill in.

The same $3,000 behaves differently in three states. Texas treats it as monthly net resources and takes 20% of it for one child, which is $600.00 a month. Nevada reads gross income through a stack of brackets: at $12,000 a month the same child comes to $1,360.00, and that figure is the sum of the percentages each bracket prints, not one rate applied to the whole income. Virginia does not multiply a share at all: it looks a printed dollar row up on both parents' combined income and then divides the row between them, so $3,000 and $3,000 come to 50% each and $500 a month for the parent paying support.

Four shapes, one question: what gets multiplied

Every guideline in this tool is one of four shapes, and the shape decides what the arithmetic even is. A flat table publishes one percentage per number of children and multiplies the base once. A tiered table splits the base into brackets and gives each bracket its own percentage, so the effective share falls as income rises. A printed schedule publishes the dollar amounts themselves, one row per income band and one column per child, so there is nothing to multiply - only a row to find. A worksheet publishes lines, not a table, and several of those lines are blank until a family or a court fills them in.

The worksheet is where the family’s own numbers enter

A table can only multiply what it is given, so everything a household actually pays for - health cover, child care, the nights a child spends in each home - lives outside the table. Two of those costs sit on worksheet lines 7.b and 7.c in Virginia: the health coverage line is measured against a reasonable-cost test before it is added, and the child care line is taken at whichever figure is less. Both are added before the row is divided between the parents, which is why they move the answer by less than the amount entered.

Missouri’s Form No. 14 goes further: line 6a credits a share of the receiving parent’s child care, line 10 credits the costs the paying parent already carries, and line 11 applies the overnight table to line 5 before line 12 is printed. With $4,000 and $2,000 of monthly income and two children, line 12 comes to $1,060 a month - a figure that is not any table’s row but the output of twelve lines, each of which can be checked against the form. Parenting time is a line on that worksheet rather than a share of the total, and the form’s own caveat can withhold the table entirely when the incomes are too low for it.

The base matters more than the percentage

Before any share is applied, each state decides what is being shared. Texas multiplies net resources - income after the deductions its own rules allow - which is why the tool asks for that figure rather than a salary. Nevada multiplies gross income. Virginia and Georgia look their schedules up on the parents’ combined income and then divide, because their sections say the obligation belongs to the child and the two incomes carry it in proportion. A pay stub rarely shows a month, so the page offers the four conversions Virginia’s worksheet prints: a $693 weekly figure becomes $3,000.69 before the worksheet’s rounding, and then the schedule is read with the rounded figure.

Where these numbers come from

• Every figure above is calculated, not copied in. The four shapes, the caps, the brackets, the printed rows and the twelve worksheet lines are all handled by the same child support calculation, and the published percentages and dollar amounts come from one checked table of official figures, one entry per state with the official page it was read from. The Child Support Calculatorand this guide use that same calculation, so they cannot print two different answers.
• Every release automatically checks the math against each state's own publication: the share applied is the one that state publishes (a flat percentage, a bracket sum, a G 1 proportion), the Form No. 14 lines add back up to line 12, and the CSV a visitor downloads carries one row per payment and the same annual figure the answer prints. A separate check compares every published number with the official text we keep and confirms the file has not changed since it was recorded.
• The statutes are cited, not paraphrased into something friendlier. Texas Family Code Sec. 154.125, Nevada NAC 425.140, Code of Virginia § 20-108.2 and Missouri Supreme Court Rule 88.01 are named in the state's own text, and the page prints the line numbers those documents give rather than inventing its own.

What this guide does not cover

It does not decide an order. Every figure here is a presumptive amount: a court may deviate upward or downward on the evidence, and that decision is not arithmetic any table can do. It does not compute the base from a wage - net resources, the deductions that produce them and self-employment income are decided before the table sees a number, which is why the tool asks for the base rather than a salary. It does not cover shared parenting formulas (their own arithmetic in most states), medical support orders, travel between two homes, or who claims a child for tax purposes. And it does not replace the state’s worksheet: where a family’s own figures are needed, this page asks for them, and the answer is only as good as what was entered.

Estimate one in the Child Support Calculator, or work out the income that goes in with the Paycheck Calculator.

Explanations only - not legal advice for any particular case. Read the full disclaimer.