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Abhishek Gurjar
Abhishek Gurjar

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Build a Mortgage Calculator Website

Introduction

Hello, developers! I’m thrilled to share my latest project: a Mortgage Calculator. This project is ideal for those who want to build a practical, interactive web application that calculates mortgage payments using HTML, CSS, and JavaScript. It’s a fantastic way to enhance your frontend development skills and create a useful tool for personal finance management.

Project Overview

The Mortgage Calculator is a web application designed to help users calculate their mortgage payments and total repayment amounts. With a clean and intuitive interface, this project showcases how to create a functional and interactive web tool that can be used in real-life scenarios.

Features

  • Interactive Calculator: Users can input mortgage amount, term, and interest rate to get accurate calculations.
  • Repayment Options: Offers options for both principal and interest payments and interest-only payments.
  • Responsive Design: The application is fully responsive, ensuring it works well on both desktop and mobile devices.

Technologies Used

  • HTML: Provides the structure for the Mortgage Calculator.
  • CSS: Styles the application to ensure it is visually appealing and user-friendly.
  • JavaScript: Adds interactivity and performs the mortgage calculations based on user input.

Project Structure

Here’s an overview of the project structure:

Mortgage-Calculator/
├── index.html
├── style.css
└── script.js
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  • index.html: Contains the HTML structure for the Mortgage Calculator.
  • style.css: Includes CSS styles to create a modern and responsive design.
  • script.js: Manages the interactive elements and performs the mortgage calculations.

Installation

To get started with the project, follow these steps:

  1. Clone the repository:

    git clone https://github.com/abhishekgurjar-in/Mortgage-Calculator.git
    
  2. Open the project directory:

    cd Mortgage-Calculator
    
  3. Run the project:

    • Open the index.html file in a web browser to view the Mortgage Calculator.

Usage

  1. Open the website in a web browser.
  2. Input the mortgage amount, term, and interest rate into the respective fields.
  3. Select the repayment option (Principal & Interest or Interest Only).
  4. Click on the Calculate button to see the monthly and total repayments.
  5. View the responsive design by resizing the browser window or opening the website on different devices.

Code Explanation

HTML

The index.html file defines the structure of the Mortgage Calculator, including input fields, buttons, and result display areas. Here’s a snippet:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Mortgage Calculator</title>
  <link href="https://fonts.googleapis.com/css?family=Plus+Jakarta+Sans:400,600&display=swap" rel="stylesheet">
  <link rel="stylesheet" href="style.css">
  <script src="./script.js" defer></script>
</head>
<body>
  <div class="container">
    <div class="box">
      <div class="left-box">
        <h1>Mortgage Calculator</h1>
        <p>Calculate your mortgage payments easily with this interactive tool. Enter the details below to find out your monthly and total repayments.</p>
        <div class="input-box">
          <span>£</span><input type="number" class="MortgageAmount" placeholder="Mortgage Amount">
        </div>
        <div class="input-box">
          <span>Years</span><input type="number" class="MortgageTerm" placeholder="Mortgage Term">
        </div>
        <div class="input-box">
          <span>%</span><input type="number" class="Interest" placeholder="Annual Interest Rate">
        </div>
        <div class="box-middle">
          <input type="radio" id="Repayment" name="repayment" class="option" checked>
          <label for="Repayment">Principal & Interest</label>
          <input type="radio" id="InterestOnly" name="repayment" class="option">
          <label for="InterestOnly">Interest Only</label>
        </div>
        <button class="calculate">Calculate</button>
        <div class="empty-result">
          <p>Fill out the form to see your results.</p>
        </div>
        <div class="filled-result">
          <h1>£0.00</h1>
          <h4>Total Repayment: £0.00</h4>
        </div>
      </div>
    </div>
    <div class="footer">
      <p>Made with ❤️ by Abhishek Gurjar</p>
    </div>
  </div>
</body>
</html>
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CSS

The style.css file styles the Mortgage Calculator, making it attractive and easy to use. Below are some key styles:

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-size: 16px;
  background-color: hsl(202, 86%, 94%);
}

.container {
  margin: auto;
  max-width: 1440px;
  background-color: hsl(202, 86%, 94%);
}

.box {
  border-radius: 20px;
  background-color: whitesmoke;
  max-width: 900px;
  margin: 160px auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.left-box {
  width: 50%;
}

.left-box h1 {
  font-size: 2.5rem;
}

.left-box p {
  font-size: 1rem;
}

.input-box {
  width: 80%;
  border: 1px solid black;
  border-radius: 4px;
  display: flex;
  align-items: center;
}

.input-box span {
  width: 20px;
}

.input-box input {
  width: 70%;
  height: 100%;
  border: none;
}

.calculate {
  background-color: yellow;
  width: 50%;
  border-radius: 8px;
  height: 2.5rem;
  margin: 15px;
}

.empty-result {
  border-radius: 20px;
  padding: 10px;
  color: white;
  background-color: #1b3547;
}

.filled-result {
  display: none;
}

.footer {
  margin-top: 100px;
  text-align: center;
}

@media (max-width: 800px) {
  .box {
    flex-direction: column;
    align-items: center;
    gap: 100px;
  }
}
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JavaScript

The script.js file contains the logic for calculating mortgage payments based on user input. Here’s a snippet:

document.addEventListener('DOMContentLoaded', () => {
    const calculateButton = document.querySelector('.calculate');
    const emptyResult = document.querySelector('.empty-result');
    const filledResult = document.querySelector('.filled-result');
    const mortgageAmountInput = document.querySelector('.MortgageAmount');
    const mortgageTermInput = document.querySelector('.MortgageTerm');
    const interestRateInput = document.querySelector('.Interest');
    const repaymentOption = document.querySelector('#Repayment');
    const interestOnlyOption = document.querySelector('#InterestOnly');
    const monthlyRepaymentElement = filledResult.querySelector('h1');
    const totalRepaymentElement = filledResult.querySelector('h4');

    calculateButton.addEventListener('click', () => {
      const principal = parseFloat(mortgageAmountInput.value);
      const years = parseFloat(mortgageTermInput.value);
      const annualInterestRate = parseFloat(interestRateInput.value) / 100;
      const months = years * 12;
      let monthlyRepayment;
      let totalRepayment;

      if (repaymentOption.checked) {
        const monthlyInterestRate = annualInterestRate / 12;
        monthlyRepayment = (principal * monthlyInterestRate) / (1 - Math.pow(1 + monthlyInterestRate, -months));
        totalRepayment = monthlyRepayment * months;
      } else if (interestOnlyOption.checked) {
        monthlyRepayment = (principal * annualInterestRate) / 12;
        totalRepayment = principal + (monthlyRepayment * months);
      }

      if (!isNaN(monthlyRepayment) && !isNaN(totalRepayment)) {
        monthlyRepaymentElement.textContent = ${monthlyRepayment.toFixed(2)}`;
        totalRepaymentElement.textContent = ${totalRepayment.toFixed(2)}`;
        emptyResult.style.display = 'none';
        filledResult.style.display = 'block';
      } else {
        alert('Please enter valid numbers for all fields.');
      }
    });
});
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Live Demo

You can check out the live demo of the Mortgage Calculator project here.

Conclusion

Creating the Mortgage Calculator was a valuable exercise in applying frontend development skills to build a practical tool. This project demonstrates how to create an interactive and responsive web application that can be used for financial planning. I hope it inspires you to build your own tools and enhance your web development skills. Happy coding!

Credits

This project was developed as part of my continuous learning journey in web development.

Author

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