Online HTML, CSS & JS Editor
Write HTML, CSS and JavaScript and see a live preview as you type. Your code autosaves in this browser and downloads as one HTML file — a free, no-login CodePen alternative.
Quick Links
A free online HTML editor with live preview
This online HTML, CSS and JavaScript editor lets you write all three languages side by side and watch the result render in a live preview as you type — no setup, no install, no account. It opens instantly, so you can go from an idea to a working demo in seconds: prototype a component, test a snippet from a tutorial, reproduce a bug, or practise for a front-end interview.
The default modern view is a split-screen IDE — your code on the left with HTML, CSS and JS tabs, and a browser-style live preview on the right. Prefer everything on one screen? Switch to classic view, or open focus mode to fill the screen and lock page scrolling while you code. Your work is autosaved in this browser, and the Download button exports it as a single index.html file you can open anywhere or upload to any host.
How to use the online HTML editor
1 · Write your code
Type HTML, CSS and JavaScript in their tabs, or pick a starter template to begin from a working example.
2 · See it live
The preview updates as you type. Use Run to re-execute scripts or Reload to refresh the preview panel.
3 · Keep or share it
Your code autosaves as you go. Press Download to get one complete HTML file with your CSS and JavaScript inside.
This editor vs CodePen
CodePen is the best-known front-end playground, and it is the better choice when you want a public portfolio, preprocessors or a community. This editor is built for the other case: a quick, private test with nothing to sign up for.
| Feature | This editor | CodePen |
|---|---|---|
| Account needed | No | Only to save pens |
| Where your code lives | Only in your browser | On CodePen's servers |
| Saving | Autosave in this browser, download as HTML | Saved pens in your account |
| Public share links | No | Yes |
| Preprocessors (Sass, TypeScript) | No, plain HTML, CSS and JS | Yes |
| Starter templates | 9 built in | Templates and community pens |
| Price | Free, no limits | Free tier, Pro plans |
What you can build here
Anything that runs in a single web page. Each starter template is a complete, working example you can take apart:
- Layouts — a responsive CSS grid that reflows from four columns to one, and reusable card components.
- Forms — a styled contact form to test labels, focus states and validation messages.
- Animation — CSS keyframes and transitions you can tune and watch instantly.
- Interactivity — a modal window, a click counter, an image gallery and a to-do list written in plain JavaScript, with no framework to install.
Scripts and stylesheets from a CDN also work: add a <script src> or <link> tag in the HTML pane to try a library before you add it to a project.
Why use this online code editor?
- Modern split-screen IDE — code on the left, a live browser-style preview on the right.
- Instant & no login — open the page and start coding; nothing to install or sign up for.
- Real-time preview — HTML, CSS and JS combine into a live result as you type, external images and scripts included.
- Focus mode — full-screen workspace that locks page scrolling so you can concentrate on code.
- Nine starter templates — forms, cards, animations, a modal, an image gallery, a to-do app and more.
- Autosave and download — work survives a reload, and one click exports a complete HTML file.
- Private & responsive — your code runs in your browser and the layout works on any device.
Who uses a code playground like this?
Developers
Prototype a component or reproduce a bug in seconds, without spinning up a project.
Students & learners
Practise HTML, CSS and JavaScript with instant feedback — the fastest way to learn front-end.
Teachers & interviewers
Demonstrate concepts live or run quick front-end coding exercises with no setup.
Frequently asked questions
Is this online code editor free?
Yes — completely free, with no login, no signup and no usage limits. Open the page and start writing HTML, CSS and JavaScript straight away.
Do I need an account to use it?
No. You can code and see the live preview instantly without signing in — a fast, no-login CodePen alternative that runs in your browser.
Does my code stay private?
Yes. Everything runs locally in your browser; your HTML, CSS and JavaScript are not uploaded to any server.
What is the difference between modern and classic view?
Modern view is a split-screen IDE — code on the left with HTML/CSS/JS tabs and a live browser-style preview on the right. Classic view stacks the three editors above the preview. Focus mode expands the workspace to fill the screen and locks page scrolling.
Can I use the starter templates?
Yes — choose from nine ready-made templates and edit them however you like: basic page, contact form, card, CSS animation, responsive grid, interactive button, modal, image gallery and a to-do app.
How is the live preview generated?
The editor combines your HTML, CSS and JavaScript and renders them together inside a preview frame in real time, so you see the result update as you type.
Is my code saved if I close the tab?
Yes, on the same browser and device. The editor autosaves your HTML, CSS and JavaScript in your browser storage as you type and restores them when you come back. Private windows and cleared site data start empty, so download anything you want to keep.
Can I download my code as an HTML file?
Yes. The Download button combines your HTML, CSS and JavaScript into one complete index.html file that opens in any browser or can be uploaded to any web host.
Does it work on mobile?
Yes. The editor is fully responsive; the split view stacks on smaller screens so you can write code and preview it on a phone or tablet.
Is this the same as CodePen?
No. It is an independent, free online code editor built on the same idea — a quick HTML, CSS and JavaScript playground with an instant preview. It is not affiliated with CodePen. Use CodePen when you want public pens, preprocessors and a community; use this editor when you want to test something privately with no account.
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