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.
This page documents the HTTP endpoint POST /api/tools/fire-calculator/execute. See the MCP reference →
Call it over REST
POST https://api.findutils.com/api/tools/fire-calculator/execute · no API keys · 60 requests/min per IP
Execute — verified arguments
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 for this endpoint
curl https://api.findutils.com/api/tools/fire-calculatorInput 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)
{
"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"
}Also an MCP tool
Claude, Cursor, and any MCP client can call this tool as
findutils:fire_calculator after one connect command.
Connect once
claude mcp add findutils --transport http https://mcp.findutils.com/More Finance tools
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