---
title: "Compound Interest Calculator"
method: POST
path: "/api/v1/tools/compound-interest-calculator"
tags: ["tools"]
---

# Compound Interest Calculator

`POST /api/v1/tools/compound-interest-calculator`

## Request

- Base URL: `https://toolforte.com`
- URL: `https://toolforte.com/api/v1/tools/compound-interest-calculator`
- Auth: HTTP bearer

Grow a starting amount at an annual rate for a number of years, compounding monthly, quarterly or annually, with an optional monthly contribution. Returns the future value, total contributed, total interest and a year-by-year table.

## Request body

- object
  - `principal` integer
  - `annualRatePercent` integer
  - `years` integer
  - `compoundsPerYear` integer
  - `monthlyContribution` integer

## Response `200`

Successful result

- object
  - `ok` boolean
  - `data` object
    - `principal` integer
    - `annualRatePercent` integer
    - `years` integer
    - `compoundsPerYear` integer
    - `monthlyContribution` integer
    - `futureValue` number
    - `totalContributed` integer
    - `totalInterest` number
    - `interestPercent` number
    - `yearly` object[]
      - `year` integer
      - `contributions` integer
      - `interest` number
      - `balance` number

## Other responses

- `400`: Missing or invalid request fields
- `401`: Invalid or missing API key
- `429`: Monthly plan limit reached

---

[API](https://skmtc.dev/toolforte/apis/toolforte-api.md) · [All operations](https://skmtc.dev/toolforte/apis/toolforte-api/llms.txt) · [OpenAPI document](https://skmtc.dev/toolforte/apis/toolforte-api/revisions/4d814d484dfc?raw)