Compute compound interest growth. Supports any compound frequency (monthly, quarterly, annual) plus optional fixed monthly contributions. Returns final balance, total contributions, total interest, and a year-by-year balance series.
This page documents the HTTP endpoint POST /api/tools/compound-interest/execute. See the MCP reference →
Call it over REST
POST https://api.findutils.com/api/tools/compound-interest/execute · no API keys · 60 requests/min per IP
Execute — verified arguments
curl -X POST https://api.findutils.com/api/tools/compound-interest/execute \
-H "Content-Type: application/json" \
-d '{
"principal": 1000,
"annual_rate": 0.05,
"years": 5
}'Parameter schema for this endpoint
curl https://api.findutils.com/api/tools/compound-interestInput schema
| Argument | Type | Required | Description |
|---|---|---|---|
| principal | number | yes | Starting principal (in any currency). |
| annual_rate | number | yes | Annual interest rate as a decimal (0.07 = 7%). |
| years | number | yes | Investment duration in years. |
| compounds_per_year | integer | no | Compound periods per year. Default: 12 (monthly). |
| monthly_contribution | number | no | Optional fixed monthly contribution. Default: 0. |
Example arguments (verified)
{
"principal": 1000,
"annual_rate": 0.05,
"years": 5
}Also an MCP tool
Claude, Cursor, and any MCP client can call this tool as
findutils:compound_interest after one connect command.
Connect once
claude mcp add findutils --transport http https://mcp.findutils.com/More Finance tools
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