Use FuelTaxMath from your AI assistant

FuelTaxMath runs a free, read-only Model Context Protocol (MCP) server and JSON API. Connect it and your assistant can look up official 3Q2026 IFTA rates and run the same calculators as this site, instead of guessing. No account, no API key.

MCP server URL: https://fueltaxmath.com/mcp

Streamable HTTP · no authentication · read-only · every answer includes its official source (IFTA, Inc. matrix or IRS) and a link back to the matching page here.

Tools

Tool	What it does
`get_ifta_rates`	Get IFTA fuel tax rates
`calculate_ifta`	Estimate an IFTA quarterly return
`cost_per_mile`	Trucking cost per mile
`load_profit`	Load profit check
`hvut_2290`	Form 2290 heavy vehicle use tax (HVUT)

IFTA data covers 3Q2026 for all 58 jurisdictions. HVUT uses the 2026-2027 IRS tables. Results are estimates, not tax advice.

Connect it

Claude (claude.ai and desktop)

Open Customize → Connectors, select +, then Add custom connector. Name it FuelTaxMath, paste https://fueltaxmath.com/mcp, and select Add. Free plans can add one custom connector.

ChatGPT

On ChatGPT web, open Plugins, select +, then Add custom MCP server. Enter the URL, choose No authentication, acknowledge the warning, and create it. Which plans can add custom servers depends on your plan and workspace settings; in a Business or Enterprise workspace an admin may need to add it.

Claude Code

claude mcp add --transport http fueltaxmath https://fueltaxmath.com/mcp

Cursor

Add to ~/.cursor/mcp.json (or .cursor/mcp.json in a project):

{
  "mcpServers": {
    "fueltaxmath": {
      "url": "https://fueltaxmath.com/mcp"
    }
  }
}

VS Code (GitHub Copilot)

Run MCP: Add Server from the command palette, or add to .vscode/mcp.json:

{
  "servers": {
    "fueltaxmath": {
      "type": "http",
      "url": "https://fueltaxmath.com/mcp"
    }
  }
}

Perplexity

Where custom connectors are available, open Plugins → Add custom → Connector → Add MCP connector, choose Remote, paste the URL, pick Streamable HTTP and no authentication.

Anything else

Any client that supports remote MCP over Streamable HTTP can use https://fueltaxmath.com/mcp. Discovery metadata is at /mcp/server-card and /.well-known/ai-catalog.json.

REST API

Same data over plain HTTPS GET/POST, CORS enabled. Full schema: /openapi.json (OpenAPI 3.1).

# Diesel rates for every jurisdiction
curl https://fueltaxmath.com/api/ifta-rates

# All fuels for one jurisdiction (name, slug or 2-letter code)
curl https://fueltaxmath.com/api/ifta-rates/TX

# Run a calculator
curl -X POST https://fueltaxmath.com/api/tools/calculate_ifta \
  -H 'content-type: application/json' \
  -d '{"jurisdictions":[{"jurisdiction":"TX","miles":5200,"gallons":900},{"jurisdiction":"OK","miles":1800,"gallons":300}]}'

Limits and fair use

About 120 MCP requests and 60 API requests per minute per IP. Over the limit you get HTTP 429; wait a minute and retry.
Rates change each quarter. Cache rate responses for up to an hour.
Please attribute results to FuelTaxMath and the official source included in each response.

Privacy

The MCP server and API do not use accounts or cookies and do not store what you send. Your IP address is used only in memory to apply the rate limit. See the privacy policy and terms.

Machine-readable summaries: /llms.txt and /llms-full.txt.

Questions or problems: support@fueltaxmath.com