Return a full loan amortization schedule (one row per month with payment, principal, interest, extra payment, balance) plus totals, interest saved, months saved, and the payoff month. Rate is a yearly percentage; payments are monthly.
This page documents the HTTP endpoint POST /api/tools/amortization-calculator/execute. See the MCP reference →
Call it over REST
POST https://api.findutils.com/api/tools/amortization-calculator/execute · no API keys · 60 requests/min per IP
Execute — verified arguments
curl -X POST https://api.findutils.com/api/tools/amortization-calculator/execute \
-H "Content-Type: application/json" \
-d '{
"loan_amount": 250000,
"interest_rate": 6.5,
"loan_term_years": 30,
"start_month": "2026-01"
}'Parameter schema for this endpoint
curl https://api.findutils.com/api/tools/amortization-calculatorInput schema
| Argument | Type | Required | Description |
|---|---|---|---|
| loan_amount | number | yes | Loan principal. |
| interest_rate | number | yes | Yearly interest rate in percent (6.5 = 6.5%). Must be > 0. |
| loan_term_years | integer | yes | Loan term in years (1-40). |
| extra_payment | number | no | Optional extra principal paid every month. Default: 0. |
| start_month | string | no | First payment month as YYYY-MM. Default: the current UTC month. |
Example arguments (verified)
{
"loan_amount": 250000,
"interest_rate": 6.5,
"loan_term_years": 30,
"start_month": "2026-01"
}Also an MCP tool
Claude, Cursor, and any MCP client can call this tool as
findutils:amortization_calculator after one connect command.
Connect once
claude mcp add findutils --transport http https://mcp.findutils.com/More Finance tools
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