Loan CalculatorLoan Calculator API

OnlineCredit Usage:1 per callRefreshed 1 month ago
avg: 908ms|p50: 848ms|p75: 948ms|p90: 1068ms|p99: 1308ms

Loan Payment Calculator is a simple tool for calculating loan payments. It returns the monthly payment, total interest, and more.

The Loan Calculator API provides reliable and fast access to loan calculator data through a simple REST interface. Built for developers who need consistent, high-quality results with minimal setup time.

To use Loan Calculator, you need an API key. You can get one by creating a free account and visiting your dashboard.

POST Endpoint

URL
https://api.apiverve.com/v1/loanpaymentcalculator

Code Examples

Here are examples of how to call the Loan Calculator API in different programming languages:

cURL Request
curl -X POST \
  "https://api.apiverve.com/v1/loanpaymentcalculator" \
  -H "X-API-Key: your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '{
  "loanAmount": 32000,
  "interestRate": 8.5,
  "loanTerm": 6
}'
JavaScript (Fetch API)
const response = await fetch('https://api.apiverve.com/v1/loanpaymentcalculator', {
  method: 'POST',
  headers: {
    'X-API-Key': 'your_api_key_here',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    "loanAmount": 32000,
    "interestRate": 8.5,
    "loanTerm": 6
})
});

const data = await response.json();
console.log(data);
Python (Requests)
import requests

headers = {
    'X-API-Key': 'your_api_key_here',
    'Content-Type': 'application/json'
}

payload = {
    "loanAmount": 32000,
    "interestRate": 8.5,
    "loanTerm": 6
}

response = requests.post('https://api.apiverve.com/v1/loanpaymentcalculator', headers=headers, json=payload)

data = response.json()
print(data)
Node.js (Native HTTPS)
const https = require('https');
const url = require('url');

const options = {
  method: 'POST',
  headers: {
    'X-API-Key': 'your_api_key_here',
    'Content-Type': 'application/json'
  }
};

const postData = JSON.stringify({
  "loanAmount": 32000,
  "interestRate": 8.5,
  "loanTerm": 6
});

const req = https.request('https://api.apiverve.com/v1/loanpaymentcalculator', options, (res) => {
  let data = '';
  res.on('data', (chunk) => data += chunk);
  res.on('end', () => console.log(JSON.parse(data)));
});

req.write(postData);
req.end();
PHP (cURL)
<?php

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL, 'https://api.apiverve.com/v1/loanpaymentcalculator');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'X-API-Key: your_api_key_here',
    'Content-Type: application/json'
]);

curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode({
    'loanAmount': 32000,
    'interestRate': 8.5,
    'loanTerm': 6
}));

$response = curl_exec($ch);
curl_close($ch);

$data = json_decode($response, true);
print_r($data);

?>
Go (net/http)
package main

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

func main() {
    payload := map[string]interface{}{
        "loanAmount": "32000",
        "interestRate": "8.5",
        "loanTerm": "6"
    }

    jsonPayload, _ := json.Marshal(payload)
    req, _ := http.NewRequest("POST", "https://api.apiverve.com/v1/loanpaymentcalculator", bytes.NewBuffer(jsonPayload))

    req.Header.Set("X-API-Key", "your_api_key_here")
    req.Header.Set("Content-Type", "application/json")

    client := &http.Client{}
    resp, err := client.Do(req)
    if err != nil {
        panic(err)
    }
    defer resp.Body.Close()

    body, _ := io.ReadAll(resp.Body)
    fmt.Println(string(body))
}
Ruby (Net::HTTP)
require 'net/http'
require 'json'

uri = URI('https://api.apiverve.com/v1/loanpaymentcalculator')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true

payload = {
  "loanAmount": 32000,
  "interestRate": 8.5,
  "loanTerm": 6
}

request = Net::HTTP::Post.new(uri)
request['X-API-Key'] = 'your_api_key_here'
request['Content-Type'] = 'application/json'

request.body = payload.to_json

response = http.request(request)
puts JSON.pretty_generate(JSON.parse(response.body))
C# (HttpClient)
using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

class Program
{
    static async Task Main(string[] args)
    {
        using var client = new HttpClient();
        client.DefaultRequestHeaders.Add("X-API-Key", "your_api_key_here");

        var jsonContent = @"{
        ""loanAmount"": 32000,
        ""interestRate"": 8.5,
        ""loanTerm"": 6
}";
        var content = new StringContent(jsonContent, Encoding.UTF8, "application/json");

        var response = await client.PostAsync("https://api.apiverve.com/v1/loanpaymentcalculator", content);
        response.EnsureSuccessStatusCode();

        var responseBody = await response.Content.ReadAsStringAsync();
        Console.WriteLine(responseBody);
    }
}

Authentication

The Loan Calculator API requires authentication via API key. Include your API key in the request header:

Required Header
X-API-Key: your_api_key_here

Learn more about authentication →

Interactive API Playground

Test the Loan Calculator API directly in your browser with live requests and responses.

Parameters

The following parameters are available for the Loan Calculator API:

Calculate Loan Payment

ParameterTypeRequiredDescriptionDefaultExample
loanAmountnumberrequired
The loan amount
Range: min: 0
-20000
interestRatenumberrequired
The interest rate (percentage)
Range: 0 - 100
-5.5
loanTermintegerrequired
The loan term in years
Range: 1 - 50
-5

Response

The Loan Calculator API returns responses in JSON, XML, YAML, and CSV formats:

Example Responses

JSON Response
200 OK
{
  "status": "ok",
  "error": null,
  "data": {
    "loanAmount": 32000,
    "downpayment": 0,
    "interestRate": 8.5,
    "loanTerm": 6,
    "monthly_payment": 568.91,
    "total_interest_paid": 8961.4,
    "total_payment": 40961.52,
    "interestRatio": 21.88,
    "formatted": {
      "loanAmount": "$32,000.00",
      "monthlyPayment": "$568.91",
      "totalInterestPaid": "$8,961.40",
      "totalPayment": "$40,961.52"
    },
    "amortization_schedule": [
      {
        "month": 1,
        "interest_payment": 226.67,
        "principal_payment": 342.24,
        "remaining_balance": 31657.76
      },
      {
        "month": 2,
        "interest_payment": 224.24,
        "principal_payment": 344.67,
        "remaining_balance": 31313.09
      },
      {
        "month": 3,
        "interest_payment": 221.8,
        "principal_payment": 347.11,
        "remaining_balance": 30965.99
      }
    ]
  }
}
XML Response
200 OK
<?xml version="1.0" encoding="UTF-8"?>
<response>
  <status>ok</status>
  <error xsi:nil="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/>
  <data>
    <loanAmount>32000</loanAmount>
    <downpayment>0</downpayment>
    <interestRate>8.5</interestRate>
    <loanTerm>6</loanTerm>
    <monthly_payment>568.91</monthly_payment>
    <total_interest_paid>8961.4</total_interest_paid>
    <total_payment>40961.52</total_payment>
    <interestRatio>21.88</interestRatio>
    <formatted>
      <loanAmount>$32,000.00</loanAmount>
      <monthlyPayment>$568.91</monthlyPayment>
      <totalInterestPaid>$8,961.40</totalInterestPaid>
      <totalPayment>$40,961.52</totalPayment>
    </formatted>
    <amortization_schedule>
      <item>
        <month>1</month>
        <interest_payment>226.67</interest_payment>
        <principal_payment>342.24</principal_payment>
        <remaining_balance>31657.76</remaining_balance>
      </item>
      <item>
        <month>2</month>
        <interest_payment>224.24</interest_payment>
        <principal_payment>344.67</principal_payment>
        <remaining_balance>31313.09</remaining_balance>
      </item>
      <item>
        <month>3</month>
        <interest_payment>221.8</interest_payment>
        <principal_payment>347.11</principal_payment>
        <remaining_balance>30965.99</remaining_balance>
      </item>
    </amortization_schedule>
  </data>
</response>
YAML Response
200 OK
status: ok
error: null
data:
  loanAmount: 32000
  downpayment: 0
  interestRate: 8.5
  loanTerm: 6
  monthly_payment: 568.91
  total_interest_paid: 8961.4
  total_payment: 40961.52
  interestRatio: 21.88
  formatted:
    loanAmount: $32,000.00
    monthlyPayment: $568.91
    totalInterestPaid: $8,961.40
    totalPayment: $40,961.52
  amortization_schedule:
    - month: 1
      interest_payment: 226.67
      principal_payment: 342.24
      remaining_balance: 31657.76
    - month: 2
      interest_payment: 224.24
      principal_payment: 344.67
      remaining_balance: 31313.09
    - month: 3
      interest_payment: 221.8
      principal_payment: 347.11
      remaining_balance: 30965.99
CSV Response
200 OK
keyvalue
loanAmount32000
downpayment0
interestRate8.5
loanTerm6
monthly_payment568.91
total_interest_paid8961.4
total_payment40961.52
interestRatio21.88
formatted{loanAmount:$32,000.00,monthlyPayment:$568.91,totalInterestPaid:$8,961.40,totalPayment:$40,961.52}
amortization_schedule[{month:1,interest_payment:226.67,principal_payment:342.24,remaining_balance:31657.76},{month:2,interest_payment:224.24,principal_payment:344.67,remaining_balance:31313.09},{month:3,interest_payment:221.8,principal_payment:347.11,remaining_balance:30965.99}]

Response Structure

All API responses follow a consistent structure with the following fields:

FieldTypeDescriptionExample
statusstringIndicates whether the request was successful ("ok") or failed ("error")ok
errorstring | nullContains error message if status is "error", otherwise nullnull
dataobject | nullContains the API response data if successful, otherwise null{...}

Learn more about response formats →

Response Data Fields

When the request is successful, the data object contains the following fields:

Response fields marked with Premium are available exclusively on paid plans.View pricing
FieldTypeSample ValueDescription
loanAmountnumber32000Original loan amount in dollars
downpaymentnumber0Down payment amount applied to loan
interestRatenumber8.5Annual interest rate as percentage
loanTermnumber6Loan repayment period in years
monthly_paymentnumber568.91Required monthly loan payment amount
total_interest_paidnumber8961.4Total interest paid over loan term
total_paymentnumber40961.52Total amount paid over entire loan term
interestRationumber21.88Percentage of total payment allocated to interest
formattedobject{...}-
â”” loanAmountPremiumstring"$32,000.00"Formatted loan amount with currency symbol
â”” monthlyPaymentPremiumstring"$568.91"Formatted monthly payment with currency symbol
â”” totalInterestPaidPremiumstring"$8,961.40"Formatted total interest paid with currency
â”” totalPaymentPremiumstring"$40,961.52"Formatted total payment amount with currency
[ ] Array items:array[3]Array of objectsMonth-by-month breakdown of payments and balances
â”” monthnumber1Payment period month number
â”” interest_paymentnumber226.67Interest portion of monthly payment
â”” principal_paymentnumber342.24Principal portion of monthly payment
â”” remaining_balancenumber31657.76Outstanding loan balance after payment

Headers

Required and optional headers for Loan Calculator API requests:

Header NameRequiredExample ValueDescription
X-API-Keyrequiredyour_api_key_hereYour APIVerve API key. Found in your dashboard under API Keys.
Acceptoptionalapplication/jsonSpecify response format: application/json (default), application/xml, or application/yaml
User-AgentoptionalMyApp/1.0Identifies your application for analytics and debugging purposes
X-Request-IDoptionalreq_123456789Custom request identifier for tracking and debugging requests
Cache-Controloptionalno-cacheControl caching behavior for the request and response

Learn more about request headers →

GraphQL AccessALPHA

Access Loan Calculator through GraphQL to combine it with other API calls in a single request. Query only the loan calculator data you need with precise field selection, and orchestrate complex data fetching workflows.

Test Loan Calculator in the GraphQL Explorer to confirm availability and experiment with queries.

Credit Cost: Each API called in your GraphQL query consumes its standard credit cost.

GraphQL Endpoint
POST https://api.apiverve.com/v1/graphql
GraphQL Query Example
query {
  loanpaymentcalculator(
    input: {
      loanAmount: 32000
      interestRate: 8.5
      loanTerm: 6
    }
  ) {
    loanAmount
    downpayment
    interestRate
    loanTerm
    monthly_payment
    total_interest_paid
    total_payment
    interestRatio
    formatted {
      loanAmount
      monthlyPayment
      totalInterestPaid
      totalPayment
    }
    amortization_schedule
  }
}

Note: Authentication is handled via the x-api-key header in your GraphQL request, not as a query parameter.

CORS Support

The Loan Calculator API supports Cross-Origin Resource Sharing (CORS) with wildcard configuration, allowing you to call Loan Calculator directly from browser-based applications without proxy servers.

CORS HeaderValueDescription
Access-Control-Allow-Origin*Accepts requests from any origin
Access-Control-Allow-Methods*Accepts any HTTP method
Access-Control-Allow-Headers*Accepts any request headers

Browser Usage: You can call Loan Calculator directly from JavaScript running in the browser without encountering CORS errors. No proxy server or additional configuration needed.

Learn more about CORS support →

Rate Limiting

Loan Calculator API requests are subject to rate limiting based on your subscription plan. These limits ensure fair usage and maintain service quality for all Loan Calculator users.

PlanRate LimitDescription
Free5 requests/minHard rate limit enforced - exceeding will return 429 errors
StarterNo LimitProduction ready - standard traffic priority
ProNo LimitProduction ready - preferred traffic priority
MegaNo LimitProduction ready - highest traffic priority

Learn more about rate limiting →

Rate Limit Headers

When rate limits apply, each Loan Calculator response includes headers to help you track your usage:

HeaderDescription
X-RateLimit-LimitMaximum number of requests allowed per time window
X-RateLimit-RemainingNumber of requests remaining in the current window
X-RateLimit-ResetUnix timestamp when the rate limit window resets

Handling Rate Limits

Free Plan: When you exceed your rate limit, Loan Calculator returns a 429 Too Many Requests status code. Your application should implement appropriate backoff logic to handle this gracefully.

Paid Plans: No rate limiting or throttling applied. All paid plans (Starter, Pro, Mega) are production-ready.

Best Practices for Loan Calculator:

  • Monitor the rate limit headers to track your Loan Calculator usage (Free plan only)
  • Cache loan calculator responses where appropriate to reduce API calls
  • Upgrade to Pro or Mega for guaranteed no-throttle Loan Calculator performance

Note: Loan Calculator rate limits are separate from credit consumption. You may have credits remaining but still hit rate limits when using Loan Calculator on Free tier.

Error Codes

The Loan Calculator API uses standard HTTP status codes to indicate success or failure:

CodeMessageDescriptionSolution
200OKRequest successful, data returnedNo action needed - request was successful
400Bad RequestInvalid request parameters or malformed requestCheck required parameters and ensure values match expected formats
401UnauthorizedMissing or invalid API keyInclude x-api-key header with valid API key from dashboard
403ForbiddenAPI key lacks permission or insufficient creditsCheck credit balance in dashboard or upgrade plan
429Too Many RequestsRate limit exceeded (Free: 5 req/min)Implement request throttling or upgrade to paid plan
500Internal Server ErrorServer error occurredRetry request after a few seconds, contact support if persists
503Service UnavailableAPI temporarily unavailableWait and retry, check status page for maintenance updates

Learn more about error handling →

Need help? Contact support with your X-Request-ID for assistance.

Integrate Loan Calculator with SDKs

Get started quickly with official Loan Calculator SDKs for your preferred language. Each library handles authentication, request formatting, and error handling automatically.

Available for Node.js, Python, C#/.NET, and Android/Java. All SDKs are open source and regularly updated.

Integrate Loan Calculator with No-Code API Tools

Connect the Loan Calculator API to your favorite automation platform without writing code. Build workflows that leverage loan calculator data across thousands of apps.

All platforms use your same API key to access Loan Calculator. Visit our integrations hub for step-by-step setup guides.

Frequently Asked Questions

How do I get an API key for Loan Calculator?
Sign up for a free account at dashboard.apiverve.com. Your API key will be automatically generated and available in your dashboard. The same key works for Loan Calculator and all other APIVerve APIs. The free plan includes 1,000 credits plus a 500 credit bonus.
How many credits does Loan Calculator cost?

Each successful Loan Calculator API call consumes credits based on plan tier. Check the pricing section above for the exact credit cost. Failed requests and errors don't consume credits, so you only pay for successful loan calculator lookups.

Can I use Loan Calculator in production?

The free plan is for testing and development only. For production use of Loan Calculator, upgrade to a paid plan (Starter, Pro, or Mega) which includes commercial use rights, no attribution requirements, and guaranteed uptime SLAs. All paid plans are production-ready.

Can I use Loan Calculator from a browser?
Yes! The Loan Calculator API supports CORS with wildcard configuration, so you can call it directly from browser-based JavaScript without needing a proxy server. See the CORS section above for details.
What happens if I exceed my Loan Calculator credit limit?

When you reach your monthly credit limit, Loan Calculator API requests will return an error until you upgrade your plan or wait for the next billing cycle. You'll receive notifications at 80% and 95% usage to give you time to upgrade if needed.

What's Next?

Continue your journey with these recommended resources

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