CAGR Calculator API

The CAGR Calculator API allows you to compute the missing value among Initial Value, Final Value, Number of Years, and CAGR (%), provided the other three are given. It is available at:

POST https://www.promptbox.cn/api/cagr.php

Request Format

The API accepts a POST request with a JSON body containing any 3 of the following 4 fields. The missing one will be calculated.

Field Type Description
initial number Initial value (e.g., investment start amount).
final number Final value (e.g., investment end amount).
years number Number of years.
cagr number Compound Annual Growth Rate in percent (e.g., 12.5).

Note: Exactly 3 fields must be provided. The API will calculate the 4th.

Example Request

{
  "initial": 1000,
  "final": 2000,
  "years": 5
}

Response Format

The API responds with a JSON object containing all 4 fields, including the calculated one.

Field Type Description
initial number Initial value (supplied or computed).
final number Final value (supplied or computed).
years number Number of years (supplied or computed, rounded to 2 decimals).
cagr number CAGR (%) (supplied or computed, rounded to 2 decimals).

Example Successful Response

{
  "initial": 1000,
  "final": 2000,
  "years": 5,
  "cagr": 14.87
}

Error Responses

If the request is invalid, the API will return an error JSON object with an explanatory message.

Status Code Description Example
400 Invalid input (e.g., not exactly 3 fields, or non-positive values). 
{
  "error": "Please provide exactly 3 fields to calculate the missing one."
}
405 Invalid HTTP method (only POST is allowed). 
{
  "error": "Only POST method is allowed."
}

Usage Notes