# Fire Calculator — REST API endpoint `fire-calculator`

Return the FIRE number (annual expenses / withdrawal rate), years to reach it, FIRE age, progress percent, monthly investment, and a year-by-year net worth projection for Traditional, Lean, Fat, Coast, or Barista FIRE. Growth uses the real return (expected return minus inflation); rates are yearly percentages.

- Category: finance
- MCP server: https://mcp.findutils.com/ (Streamable HTTP, no API keys, 120 req/min per IP)
- REST endpoint: POST https://api.findutils.com/api/tools/fire-calculator/execute (no API keys, 60 req/min per IP)
- Reference page: https://findutils.com/api/fire-calculator/
- Same tool on the other surface: https://findutils.com/mcp/fire-calculator/

## Call the endpoint (verified example)

```bash
curl -X POST https://api.findutils.com/api/tools/fire-calculator/execute \
  -H "Content-Type: application/json" \
  -d '{
    "current_age": 30,
    "current_net_worth": 50000,
    "annual_expenses": 50000,
    "annual_income": 80000,
    "savings_rate": 30,
    "expected_return": 7,
    "withdrawal_rate": 4,
    "inflation_rate": 2.5,
    "fire_type": "traditional"
  }'

# Parameter schema
curl https://api.findutils.com/api/tools/fire-calculator
```

## Input schema

| Argument | Type | Required | Description |
|---|---|---|---|
| `current_age` | integer | yes | Current age in years. |
| `current_net_worth` | number | no | Invested net worth today. Default: 0. |
| `annual_expenses` | number | yes | Yearly spending. Must be > 0. |
| `annual_income` | number | no | Yearly income. Default: 0. |
| `savings_rate` | number | no | Percent of income saved. Default: 0. |
| `expected_return` | number | no | Expected yearly return in percent. Default: 7. |
| `withdrawal_rate` | number | no | Safe withdrawal rate in percent. Must be > 0. Default: 4. |
| `inflation_rate` | number | no | Yearly inflation in percent. Default: 2.5. |
| `fire_type` | string (traditional \| lean \| fat \| coast \| barista) | no | FIRE variant. Default: traditional. |

Example arguments (verified):

```json
{
  "current_age": 30,
  "current_net_worth": 50000,
  "annual_expenses": 50000,
  "annual_income": 80000,
  "savings_rate": 30,
  "expected_return": 7,
  "withdrawal_rate": 4,
  "inflation_rate": 2.5,
  "fire_type": "traditional"
}
```

OpenAPI 3.1 spec: https://findutils.com/api/openapi.json · Interactive docs: https://findutils.com/api/docs/

## Also an MCP tool

```bash
claude mcp add findutils --transport http https://mcp.findutils.com/
```

Then ask the client to call `findutils:fire_calculator`. Full MCP reference: https://findutils.com/mcp/fire-calculator/

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