For the complete documentation index, see llms.txt.

Future Value of Annuity Calculator API

finance 2 credits / call v2026-04-22

Calculate future value for ordinary annuities and annuities due.

Use this endpoint to add Future Value of Annuity Calculator to your app, site, workflow, or agent without rebuilding formulas, validation, examples, and docs.

Prefer the browser version? Open the Future Value of Annuity Calculator on miniwebtool.com.

Start Starter → Requires Starter+ · $29/mo
Starts on Starter
Free keys can view docs and examples, but calls to this endpoint require Starter or higher.
Start Starter →
What this saves

Skip a custom implementation, validation rules, examples, OpenAPI shape, billing checks, and support copy for this utility.

Where it fits

Product forms, calculator pages, finance content, education flows, support tools, automations, and agent actions.

How to evaluate

Inspect the required fields, try the hosted playground, then copy cURL, Python, or Node code into your integration.

Endpoint

POST https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run

Request body

Field Type Req.
payment float
rate_percent float
periods int
annuity_type
ordinary | due
str
precision int

Cost & access

  • 2 credits per successful call.
  • Starts on: Starter or higher.
  • Max payload: 65536 bytes.
  • Privacy mode: hash_only
  • Available on: starter, pro, business, scale

Response envelope

{
  "request_id": "01K...",
  "tool": "future-value-of-annuity-calculator",
  "tool_version": "2026-04-22",
  "credits_used": 2,
  "result": { ... }
}

Try it

Stored only in this browser tab. Playground test key is prefilled and only works on this page. Get a live key →
ordinary | due

Code examples

curl -X POST https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run \
  -H 'Authorization: Bearer mwt_live_YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"payment":1000,"rate_percent":5,"periods":10,"annuity_type":"ordinary"}'
import requests

resp = requests.post(
    'https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run',
    headers={'Authorization': 'Bearer mwt_live_YOUR_KEY'},
    json={'payment': 1000, 'rate_percent': 5, 'periods': 10, 'annuity_type': 'ordinary'},
)
resp.raise_for_status()
print(resp.json())
const resp = await fetch(
  'https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run',
  {
    method: 'POST',
    headers: {
      'Authorization': 'Bearer mwt_live_YOUR_KEY',
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({"payment":1000,"rate_percent":5,"periods":10,"annuity_type":"ordinary"}),
  }
);
const data = await resp.json();
console.log(data);
<?php
$ch = curl_init('https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run');
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer mwt_live_YOUR_KEY',
        'Content-Type: application/json',
    ],
    CURLOPT_POSTFIELDS => json_encode([
    'payment' => 1000,
    'rate_percent' => 5,
    'periods' => 10,
    'annuity_type' => 'ordinary'
]),
]);
$resp = curl_exec($ch);
curl_close($ch);
print_r(json_decode($resp, true));
require 'net/http'
require 'json'
require 'uri'

uri = URI('https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = (uri.scheme == 'https')

req = Net::HTTP::Post.new(uri)
req['Authorization'] = 'Bearer mwt_live_YOUR_KEY'
req['Content-Type'] = 'application/json'
req.body = {
  'payment' => 1000,
  'rate_percent' => 5,
  'periods' => 10,
  'annuity_type' => 'ordinary'
}.to_json

resp = http.request(req)
puts JSON.parse(resp.body).inspect
package main

import (
  "bytes"
  "encoding/json"
  "fmt"
  "io"
  "net/http"
)

func main() {
  body, _ := json.Marshal(map[string]interface{}{
    "payment": 1000,
    "rate_percent": 5,
    "periods": 10,
    "annuity_type": "ordinary",
  })
  req, _ := http.NewRequest("POST", "https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run", bytes.NewReader(body))
  req.Header.Set("Authorization", "Bearer mwt_live_YOUR_KEY")
  req.Header.Set("Content-Type", "application/json")

  resp, err := http.DefaultClient.Do(req)
  if err != nil { panic(err) }
  defer resp.Body.Close()
  out, _ := io.ReadAll(resp.Body)
  fmt.Println(string(out))
}
import java.net.URI;
import java.net.http.*;

var client = HttpClient.newHttpClient();
var req = HttpRequest.newBuilder()
    .uri(URI.create("https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run"))
    .header("Authorization", "Bearer mwt_live_YOUR_KEY")
    .header("Content-Type", "application/json")
    .POST(HttpRequest.BodyPublishers.ofString("{\"payment\":1000,\"rate_percent\":5,\"periods\":10,\"annuity_type\":\"ordinary\"}"))
    .build();

var resp = client.send(req, HttpResponse.BodyHandlers.ofString());
System.out.println(resp.body());

How to call Future Value of Annuity Calculator

  1. 1 Get an API key
    Get an API key. Choose the Starter plan or higher to receive a bearer token with access to this endpoint.
  2. 2 Assemble the JSON body
    Required fields: payment, rate_percent, periods, . See the Request body table below for the full schema.
  3. 3 POST to https://api.miniwebtool.com/v1/tools/future-value-of-annuity-calculator/run
    Headers: Authorization: Bearer <key> and Content-Type: application/json. Copy-paste snippets in 7 languages are under Code examples.
  4. 4 Parse the response
    Envelope: {request_id, tool, tool_version, credits_used, result}. The typed output lives in result.

Frequently asked

What does the Future Value of Annuity Calculator API do?

Calculate future value for ordinary annuities and annuities due. Use it to add this utility without rebuilding formulas, validation, examples, and documentation.

How much does one call to Future Value of Annuity Calculator cost?

2 credits per successful call. Failed calls (validation errors, 5xx) don't bill.

What parameters does the Future Value of Annuity Calculator API require?

Required fields: payment, rate_percent, periods. Full schema at /v1/openapi.json.

Is the Future Value of Annuity Calculator API deterministic?

Yes — same input, same output, forever. Tool version 2026-04-22; output shape is stable within a major version.

Can an AI agent call the Future Value of Annuity Calculator API?

Yes. Connect to https://api.miniwebtool.com/v1/mcp over the Model Context Protocol. The agent discovers `future-value-of-annuity-calculator` with its JSON Schema automatically, so the model can plan while MiniWebtool handles the exact tool result.

What format does the API return?

JSON with a stable envelope: `{request_id, tool, tool_version, credits_used, result}`. Errors are RFC 7807 `application/problem+json`.

Use from an AI agent

Every endpoint on this site is also exposed via the Model Context Protocol at https://api.miniwebtool.com/v1/mcp. Claude, Cursor, and any MCP-capable agent can discover this tool (future-value-of-annuity-calculator) and its JSON Schema automatically — no client codegen.

# List tools the agent can call
curl -s https://api.miniwebtool.com/v1/mcp \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' \
 | jq '.result.tools[] | select(.name=="future-value-of-annuity-calculator")'

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