About
Civic legal infrastructure, not a product.
The TCB child support calculators are open-source implementations of state child support guidelines — seven so far: Tennessee, Mississippi, Arkansas, Alabama, Louisiana, Georgia, and Florida. Free to use, free to fork, free to audit. No signup, no paywall, no telemetry.
Mission
Good law deserves good tooling. Most states have well-developed child support guidelines. The tooling that delivers them often doesn't — a macro-enabled Excel file one computer opens and the next can't, a calculator behind a login that asks an ordinary parent for a bar number, a revenue department that tells people to search Google. And the number matters: by federal law a state's guideline figure isn't an estimate, it's the number a court starts from, the one a judge can leave only with a written finding. The law is mostly good. It rots in the layer in between. This project closes that gap with calculators that trace every line of math to the rule that authorizes it and produce filing-ready output.
Verified in the open
We check each calculator against the state's own official tool, not against our own homework. When we get something wrong, we say so and fix it where everyone can see — Louisiana had been running a superseded schedule until we caught it and moved to the state's 2025 table; Georgia's parenting-time calculation was corrected against the state's 2026 guidelines. Where a state's own tool has corrected one of ours, the site says so. Trust was never that a tool is perfect. It's that you can see the work, and someone fixes it when it's wrong.
Maintenance model
The project is maintained by TCB Law, PLLC, a Memphis- and Oxford-based law firm. It is not a TCB Law product: there is no commercial tier, no lead-capture form, and no paid version with extra features. The firm's relationship to the calculator is the same as the Linux Foundation's relationship to Linux — we build it, we maintain it, we do not gate it.
Substantive improvements come from community input. If you are a practitioner who spots a rule interpretation worth correcting, a chancellor who wants the worksheet to look different, or a developer who wants to fix a bug, file an issue or open a pull request against the repository.
Author
Built and maintained by Taylor C. Berger at TCB Law, PLLC, in Memphis and Oxford. State-specific verification notes live on the per-state about pages.
Roadmap
Seven Southeastern states are live: Tennessee, Mississippi, Arkansas, Alabama, Louisiana, Georgia, and Florida. The rest of the country is next. Nearly every state runs one of three models — income shares (the large majority), a percentage of one parent's income (a handful), or the Melson formula (three states: Delaware, Hawaii, and Montana). The engines already cover the first two; adding a state is mostly data, fixtures, and verification against that state's own tool, not new code. The one new engine — Melson — gets built when those three states come up.
Contact
Issues, corrections, contributions: taylor@tcblaw.org.
Disclaimer
These tools produce estimates based on the inputs you provide. They are not legal advice and do not create an attorney-client relationship. Outcomes in any specific case depend on facts, evidence, judicial discretion, and deviation analysis that these tools do not perform. Consult a licensed attorney in your jurisdiction before relying on any number produced by these calculators.