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Child support,
calculated right.
Every line of math cites the rule that authorizes it.
The worksheet is filing-ready. The code is public.
Pick a state to begin.
Your state's guideline isn't an estimate — by federal law it's the number a court starts from. We make that number, in the open.
Available now (7)
- Alabama — Income shares(Ala. R. Jud. Admin. 32)In verification
- Arkansas — Income shares(Ark. Sup. Ct. Admin. Order No. 10)In verification
- Florida — Income shares(Fla. Stat. § 61.30)In verification
- Georgia — Income shares(O.C.G.A. § 19-6-15)Recently corrected
Corrected the parenting-time (Schedule C) calculation against Georgia's 2026 guidelines.
- Louisiana — Income shares(La. R.S. § 9:315 et seq.)Recently corrected
Updated to Louisiana's 2025 child-support schedule (we had been running the 2021 table).
- Mississippi — Percentage of income(Miss. Code Ann. § 43-19-101)
- Tennessee — Income shares(Tenn. Comp. R. & Regs. 1240-02-04)
Planned (43)
Income shares (34)
Arizona, California, Colorado, Connecticut, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Utah, Vermont, Virginia, Washington, West Virginia, Wyoming.
Percentage of income (6)
Alaska, Nevada, New York, North Dakota, Texas, Wisconsin.
Melson formula (3)
Delaware, Hawaii, Montana.
Why every state has one of these
None of it is an accident. In 1975 the federal government built the child support enforcement program. In 1984 it told the states to write guidelines. In 1988 the Family Support Act made those guidelines a rebuttable presumption — the number the guideline produces is the number the court starts from, and a judge can depart from it only with a written finding that it would be unjust. The same law put the guidelines on a clock: every state must review them at least once every four years.
That four-year clock is why the numbers move — quietly, a state at a time. It's why a calculator has to be checked against each state's current official tool, not last cycle's. We do that in the open. When we found our Louisiana figures running on a superseded schedule, we said so and fixed it; the corrected states carry a mark, and their detail says what changed.
Most states share one model — income shares. A few use a percentage of one parent's income. Three use the Melson formula. The law is mostly good. The tools that deliver it mostly aren't. That's the gap this closes.
Why this exists
Across the seven states live today — Tennessee, Mississippi, Arkansas, Alabama, Louisiana, Georgia, and Florida — the official tools range from a macro-enabled Excel file that not every computer can run to mechanically simple calculations that rarely produce a shared worksheet a court can read. The law is on the books. Practitioners do excellent work. The tooling hasn't kept up.
These calculators are an attempt to close that gap. Every dollar number traces back to the rule that authorizes it. Every worksheet is structured the way a court expects to see it. Every line of code is open for anyone — practitioner, party, judge, academic, or competing firm — to audit, fork, or improve.
The project is maintained by TCB Law, PLLC, but it is not a TCB Law product. Civic legal infrastructure should not be proprietary. If you spot an interpretation of the rules that needs correcting in any of the live states, file an issue and we'll fix it. The calculator improves through community input, not through gatekeeping by any single firm.