Building Calculator Web App using HTML, CSS & JavaScript

Creating an unique calculator Web app using HTML, CSS and JavaScript to revolutionize online computation, the use of calculator software has expanded beyond simple arithmetic operations in the modern digital world, where performance and functionality rule supreme. A flexible and straightforward to use calculator Web tool can make all the difference whether performing difficult calculations involving mathematics, financial preparations or scientific investigation. In this through guide a remarkable calculator online application using the dynamic triad of JavaScript, CSS & HTML.

We'll examine the intricate details of create this cutting edge calculators as we explore not just the technical facets of developing for the internet but also the flawless integration of appearance as well as functionality. We'll help you throughout every move while following SEO best practices to make sure your invention receives the exposure it deserves, from the uploading of the project files though the implementation of the finished product.

Join us as we combine design and code to create a calculator Web based application that only not work wonderfully but also participate and entertains users. This tutorial will give you skills and knowledge necessary to build a calculator mobile application that has an internal presence in the digital world, whether you're an ambitious developer looking to diversity arsenal or abilities or someone who enjoys technology wanting to create a unique digital tool. Let's begin this thrilling adventure of innovation and creation!

Step 1: Setting up the framework of the project

Creating up the work environment and structure is crucial before we begin developing our creative calculator web app. You will be led throught the basic stages of developing the project and getting it ready for development in this section.

JavaScript and CSS file links make style.css and script.js files in the appropriate CSS and JavaScript folder (CSS and js respectively), include the paragraph that follows lines in your the index.html file to link the following files to your HTML. These stages link your HTML page to external JavaScript as well as CSS files and establish the fundamental project structure. You are now prepared to create the user experience and and begin addon features to your creative calculator internet based application in the section that follow.

✲ index.html

<!DOCTYPE html>
<html lang="en">
  <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <meta http-equiv="X-UA-Compatible" content="ie=edge">
     <link rel="stylesheet" href="style.css">
     <title>Calculator Web App | Coding Zemigle</title>
 </head>
 <body> 
     <div class="calculator">
        <div class="display">
             <input type="text" placeholder="0" id="input" disabled /></div><hr>
             <div class="buttons">
             <!-- Full Erase -->
             <input type="button" value="AC" id="clear"/>
             <!-- Erase Single Value -->
             <input type="button" value="DEL" id="erase"/>
             <input type="button" value="/" class="input-button"/>
             <input type="button" value="*" class="input-button"/>
             <input type="button" value="7" class="input-button"/>
             <input type="button" value="8" class="input-button"/>
             <input type="button" value="9" class="input-button"/>
             <input type="button" value="-" class="input-button"/>
             <input type="button" value="6" class="input-button"/>
             <input type="button" value="5" class="input-button"/>
             <input type="button" value="4" class="input-button"/>
             <input type="button" value="+" class="input-button"/>
             <input type="button" value="1" class="input-button"/>
             <input type="button" value="2" class="input-button"/>
             <input type="button" value="3" class="input-button"/>
             <input type="button" value="=" id="equal"/>
             <input type="button" value="0" class="input-button"/>
             <input type="button" value="." class="input-button"/>
             </div>
         </div>
         <script src="script.js"></script>
  </body>
 </html>

It's time to use JavaScript to build the fundamental calculator functionality now that the user interface for your calculator has been created. The handling of the button clicks, carring out fundamental mathematical operations (addition, substracting them, multiplication, division) and showing the result on the screen will be the main topics of the section.

*_ JavaScript's button click to the js folder and open your script.js file

*_ Include logic to instruct the letter (C) "clear" button to reset the calculator

*_ Put the logic in place so that computations are done when the "=" the button is pressed

*_ Based on the button clicked, update the current input within the buttons click event listener

To maintain your files organized start by making a project folder. Make the following subfolder inside this folder. This is the folder where you will put your CSS files. Your files thet contain JavaScript will be kept in this dictionary and pictures. Please keep all pictures that or icons you want to utilise here. In the project folder, create an HTML file. You may give it a name index.html file, the primary gateway to your calculator app will be this file. Select a coding editor of your choosing, and then open the style.css file.

✲ style.css

* {
padding: 0;
margin: 0;
box-sizing: border-box;
font-family: "Roboto Mono", monospace;
}

body {
height: 100vh;
background: linear-gradient(to bottom, #3eff8b 50%, #090C31 50%);
}

.calculator {
width: 400px;
background-color: #090C31;
padding: 50px 30px;
position: absolute;
transform: translate(-50%, -50%);
top: 50%;
left: 50%;
border-radius: solid 2px #3eff8b;
border-radius: 8px;
box-shadow: 0 20px 50px rgba(0, 5, 24, 0.4);
}

.display {
width: 100%;
}

.display input {
width: 100%;
padding: 15px 10px;
text-align: right;
border: none;
background-color: transparent;
color: #ffffff;
font-size: 35px;
}

.display input::placeholder {
color: #9490ac;
}

.buttons {
display: grid;
grid-template-columns: repeat(4, 1fr);
grid-gap: 20px;
margin-top: 40px;
}

.buttons input[type="button"] {
font-size: 20px;
padding: 17px;
border: none;
background-color: transparent;
color: #ffffff;
cursor: pointer;
border-radius: 5px;
}

.buttons input[type="button"]:hover {
box-shadow: 0 8px 25px #000d2e;
}

input[type="button"]#equal {
grid-row: span 2;
background-color: #3eff8b;
}

input[type="button"][value="0"] {
  grid-column: span 2;
}

You'll require multiplication, division, addition and substracting functions to establish basic arithmetic operations, put the following definition in the script.js file. Using these steps you have put the fundamental calculator features in place. Results from simple arithmetic operations and user-inputted integers are presented on the screen. You may learn more about include cutting-edge features and enhancing user experience in the section that follow.

Step 2: Adding Interactivity with JavaScript

Features you can include sophisticated in addition to simple arithmetic operations in order to create your calculator Web application more functional and user friendly. We will look at the creating decimal point functionality. Parenthesis support, the backspace effectiveness and handling error cases in this part. Including functionality for decimal point make a button with the id "decimal" for the decimal point </button>. Managing cases of error the handling of seperation by zero alongside additional erroneous material has already been added. To give the user helpful error massages, continue to grow your error handling.

Your calculator Web application gets more capable and user-friendly by incorporating these latest features. Now, user scan work with parentheses, decimal and the backspace button to fix input errors, you guarantee that functionalities activity, make sure thoroughly test the calculator web app project.

✲ script.js

let equal_pressed = 0;
//Refer all buttons excluding AC and DEL
let button_input = document.querySelectorAll(".input-button");
//Refer input,equal,clear and erase
let input = document.getElementById("input");
let equal = document.getElementById("equal");
let clear = document.getElementById("clear");
let erase = document.getElementById("erase");

window.onload = () => {
  input.value = "";
};

//Access each class using forEach
button_input.forEach((button_class) => {
  button_class.addEventListener("click", () => {
    if (equal_pressed == 1) {
      input.value = "";
      equal_pressed = 0;
    }
    //display value of each button
    input.value += button_class.value;
  });
});

//Solve the user's input when clicked on equal sign
equal.addEventListener("click", () => {
  equal_pressed = 1;
  let inp_val = input.value;
  try {
    //evaluate user's input
    let solution = eval(inp_val);
    //True for natural numbers
    //false for decimals
    if (Number.isInteger(solution)) {
      input.value = solution;
    } else {
      input.value = solution.toFixed(2);
    }
  } catch (err) {
    //If user has entered invalid input
    alert("Invalid Input");
  }
});

//Clear Whole Input
clear.addEventListener("click", () => {
  input.value = "";
});
//Erase Single Digit
erase.addEventListener("click", () => {
  input.value = input.value.substr(0, input.value.length - 1);
});

Making your calculator online more interesting and attractive required enhance the viewers experience. We'll look at the numbers of strategies in this part for improving the view experience as a whole. Introducing keyboard support users can enter numbers and carry out activities using their keyboard by adding keyboard support. Elegant transitions and animations to build silk and attractive interactions include CSS transitions and animations for instance, you could add animations to the result display or transitions to the button hover effects.

Step 3: Testing and resolving debugging

Testing are the crucial steps in making sure your calculator web-based application functions properly and error free. Various facets of debugging and testing your calculator will be covered in this section. To begin test your calculator manually using a variety of inputs. Check that it appropriately handles decimal points, enclosed parentheses as well as the clearing input when necessary.

Test edge cases include dividing by zero, typing extremely either small or big numbers, and using complicated equations and parentheses. Make all the functions keys as intended by extensively testing keyboard input. Optimizing the performance of the cutting edge calculator web app is a crucial task that demands your focus as you draw closer to its completion. You have the chance to optimise of your app during this stage of development to make sure it provides a simple and effective user interface, performance optimization includes a variety of methods that improve responsiveness and user-friendliness in in addition to speed.

By eliminating extraneous characters, while spaces or comments, you can shrink the size of JavaScript, HTML and CSS files. In this process utilises as UglifyJs and minifyCSS may be of great assistant. Implement caching techniques for keeping frequently accessed data. Utilize browser caching to allow reuse of previously download resources, eliminate a desire for repetitive.

Coding Zemigle

Building Calculator Web App using HTML, CSS & JavaScript

Search Filter feature using HTML, CSS and JavaScript

How to create Full Page Tabs using HTML, CSS & JavaScript

How to create Top Navigation Bar using HTML and CSS

Crafting a running Rat Loader using HTML and CSS

Building a Light & Dark Mode using HTML and CSS