Here’s a Speed Converter & Calculator built using HTML, CSS, and JavaScript. This simple app allows users to convert speed between kilometers per hour (km/h), miles per hour (mph), and meters per second (m/s).
speed-converter.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Speed Converter</title>
<style>
body {
font-family: Arial, sans-serif;
background-color: #f4f4f4;
display: flex;
justify-content: center;
align-items: center;
height: 100vh;
margin: 0;
}
.container {
background: #fff;
padding: 20px;
border-radius: 10px;
box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
text-align: center;
width: 300px;
}
h2 {
margin-bottom: 15px;
}
.input-group {
margin-bottom: 10px;
}
label {
font-weight: bold;
display: block;
}
input {
width: 100%;
padding: 8px;
margin-top: 5px;
border: 1px solid #ccc;
border-radius: 5px;
font-size: 16px;
}
</style>
</head>
<body>
<div class="container">
<h2>Speed Converter</h2>
<div class="input-group">
<label for="kmh">Kilometers per hour (km/h)</label>
<input type="number" id="kmh" oninput="convertFromKmh(this.value)">
</div>
<div class="input-group">
<label for="mph">Miles per hour (mph)</label>
<input type="number" id="mph" oninput="convertFromMph(this.value)">
</div>
<div class="input-group">
<label for="mps">Meters per second (m/s)</label>
<input type="number" id="mps" oninput="convertFromMps(this.value)">
</div>
</div>
<script>
function convertFromKmh(value) {
let kmh = parseFloat(value);
if (!isNaN(kmh)) {
document.getElementById('mph').value = (kmh * 0.621371).toFixed(2);
document.getElementById('mps').value = (kmh / 3.6).toFixed(2);
} else {
clearFields();
}
}
function convertFromMph(value) {
let mph = parseFloat(value);
if (!isNaN(mph)) {
document.getElementById('kmh').value = (mph / 0.621371).toFixed(2);
document.getElementById('mps').value = (mph / 2.23694).toFixed(2);
} else {
clearFields();
}
}
function convertFromMps(value) {
let mps = parseFloat(value);
if (!isNaN(mps)) {
document.getElementById('kmh').value = (mps * 3.6).toFixed(2);
document.getElementById('mph').value = (mps * 2.23694).toFixed(2);
} else {
clearFields();
}
}
function clearFields() {
document.getElementById('kmh').value = "";
document.getElementById('mph').value = "";
document.getElementById('mps').value = "";
}
</script>
</body>
</html>
Features:
Convert speed between km/h, mph, and m/s.
Simple and user-friendly UI.
Responsive design.
Instant conversion on input change.