Best matchsetIntervalBeginner
Analogue Clock
Create repeating updates that keep the interface moving.
Build an analogue clock →Simple Stopwatch
Build a simple stopwatch with HTML, CSS, and JavaScript while practicing setInterval and click events.
Beginner20–30 minutesHTML5CSS3JavaScript
You'll practice
setIntervalClick EventsDOM Selection
01 — What you'll build
Simple Stopwatch
This project shows you how HTML, CSS, and JavaScript work together in a simple stopwatch. You’ll connect user interactions to visible changes on the page, then practice setInterval, click events, and DOM selection as you build the complete project from scratch.
02 — Included
- Automatic timed updates
- Simple Stopwatch interface
- Responsive HTML and CSS layout
- Complete source code and live demo
03 — You'll practice
- Create repeating actions with setInterval
- Handle user clicks
- Select HTML elements from the DOM
- Update content on the page
- Work with dates and time
- Perform calculations with JavaScript
Recommended knowledge: Basic HTML and CSS, The JavaScript Date object, JavaScript functions and callbacks, Browser timers.
Complete project files
Build It from the Source Code
This project uses timed JavaScript updates.
- 1Create three files
- 2Copy the code
- 3Run
index.html
Before you run it
- Leave the tab open to see the timed behavior update.
Project structure
stopwatch/
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Stopwatch</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<div id="timer">00:00:00</div>
<div id="buttons">
<button id="start">Start</button>
<button id="stop">Stop</button>
<button id="reset">Reset</button>
</div>
<script src="index.js"></script>
</body>
</html>
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