Terms of use

Last updated October 27, 2026.

Estimates, not advice

FuelTaxMath provides calculators and published tax rates for information only. Results are estimates and are not tax, legal, or financial advice. Rates come from the official IFTA, Inc. tax matrix and IRS publications; confirm them with your base jurisdiction or the IRS before you file or make business decisions.

Free use of the API and MCP server

You may use the site, the API and MCP server for free, including in AI assistants and your own tools, as long as you stay within the rate limits, do not try to overload or disrupt the service, and attribute results to FuelTaxMath and the official source included in each response.

No warranty

The service is provided as is, without warranties of any kind, and may change or stop at any time. To the extent the law allows, FuelTaxMath is not liable for losses from using it, including penalties or interest from filing based on an estimate.

Affiliate links

See the affiliate disclosure.

Questions or problems: support@fueltaxmath.com