Simple JavaScript Calculator Using Vanilla JavaScript

In this tutorial we have made Simple JavaScript Calculator Using Vanilla JavaScript. The HTML, CSS and JavaScript code is given below.

Table of Contents

HTML Code

HTML Code is given below.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Simple JAVASCRIPT CALCULATOR</title>
</head>
<body>
<form>
<h1>SIMPLE JAVASCRIPT CALCULATOR</h1>
<input id="input1" type="text" placeholder="Enter First Number">
<input id="input2" type="text" placeholder="Enter Second Number">
<input type="submit" onclick="add()" value="ADD">
<input type="submit" onclick="sub()" value="SUBTRACT">
<input type="submit" onclick="mul()" value="MULTIPLY">
<input type="submit" onclick="div()" value="DIVIDE">
<p>HowToCodeSchool.com</p>
</form>
</body>
</html>

CSS Code

CSS Code is given below.

body {
font-family: monospace;
display: flex;
align-items:center;
justify-content: center;
height: 100vh;
margin: 0px;
background-color: #22438C;
color: #fff;
}
form {
width: 700px;
text-align: center;
}
form input[type="text"],form input[type="submit"] {
width: 100%;
padding: 20px 5px;
font-weight: 900;
box-sizing: border-box;
background-color: #fff;
color: #22438C;
border: 1px solid #aaa;
}

JavaScript Code

JavaScript Code is given below. Four different functions are used for four different mathematical operations, addition, subtraction, multiplication and division.

<script>
function add()
{
var a = document.getElementById("input1").value;
var b = document.getElementById("input2").value;
var c= parseInt(a)+parseInt(b);
alert(c);
}
function sub()
{
var a = document.getElementById("input1").value;
var b = document.getElementById("input2").value;
var c=a-b;
alert(c);
}
function mul()
{
var a = document.getElementById("input1").value;
var b = document.getElementById("input2").value;
var c=a*b;
alert(c);
}
function div()
{
var a = document.getElementById("input1").value;
var b = document.getElementById("input2").value;
var c=a/b;
alert(c);
}
</script>

Demo

Check Demo

Video Tutorial

Watch video tutorial on how to create Simple JavaScript Calculator Using HTML, CSS and JavaScript.