Investment APIWeb Calculator UI

Free Simple Interest Calculator API (2026)

Fast API for flat simple interest calculations on short-term loans, bonds, and notes.

Interactive API Playground & Live Test

GET/api/v1/simple-interest

Query Parameters

Principal amount in ₹

Annual interest rate %

Tenure in years

curl -X GET "https://fincalculator.in/api/v1/simple-interest?principal=100000&rate=8&years=3" \
  -H "Accept: application/json"
Live JSON Response (HTTP 200 OK)
Click "Execute Live API Request" below...

Request Parameters Schema

ParameterTypeRequiredDescription / Notes
principalnumberRequiredPrincipal amount in ₹
ratenumberRequiredAnnual interest rate %
yearsnumberRequiredTenure in years