HTML Sandbox
Paste code.
Run it live.
A free online HTML sandbox and playground — paste HTML, CSS, and JavaScript and run it live in your browser, instantly. No signup to test. Deploy to a real shareable URL when you want.
Rendering runs in your browser — no account needed. Deploy only if you want a shareable link.
How to Run HTML Online
- 1Paste your code
Drop HTML, CSS, and JavaScript into the sandbox above — from an editor, an AI chat, or a tutorial.
- 2See it run live
Your code executes instantly in a sandboxed iframe, exactly as it would in a real browser. No build step, no server.
- 3Tweak and re-run
Edit the code and the preview updates automatically. Iterate as fast as you can type.
- 4Optional: deploy to share
Click Deploy to publish your sandbox to a real URL like abc12345.oneclicklive.app — share it as a normal web page, not an embed.
What Can You Run in the Sandbox?
If it runs in a browser, it runs here.
Paste a complete <!DOCTYPE html> document and it runs exactly as it would as a hosted website — head, body, styles, and scripts all execute.
Inline CSS in <style> tags and JavaScript in <script> tags run in the same sandbox, so you can test a layout and its interactions in one paste.
Paste an AI code block and run it instantly. Curly smart quotes are auto-normalized so AI output renders correctly.
Paste a component as-is. The sandbox auto-detects JSX and bundles a React 18 runtime — no Babel, no build step.
Drop in a fragment to see what it does before using it. CDN libraries like Tailwind, jQuery, Chart.js, and GSAP load over HTTPS and work normally.
Test a CSS animation, a canvas demo, or a new API — then throw it away or deploy it to a real URL if it works.
HTML Sandbox vs CodePen, JSFiddle & JSBin
The difference is what happens when you share
| Tool | Run | Account | Share as |
|---|---|---|---|
| OneClickLive HTML sandboxREAL URL | Instant | None to run | Real hosted URL (a normal web page) |
| CodePen | Instant | Needed to save | Pen embed / codepen.io link |
| JSFiddle | Instant | Needed to save | Fiddle link inside their editor |
| JSBin | Instant | Optional | Bin link inside their editor |
| W3Schools Tryit | Instant | None | No real shareable link |
What Is an HTML Sandbox?
An HTML sandbox (also called an HTML playground or online code runner) is a browser-based environment where you paste HTML, CSS, and JavaScript and run it live without installing anything or setting up a server. The code executes in an isolated sandboxed iframe, so it can't touch the rest of the page — safe to test untrusted snippets, AI output, or half-finished experiments. OneClickLive adds one thing the classic sandboxes don't: when your code works, one click turns it into a real hosted website URL instead of a snippet locked inside an editor.
Playground That Becomes a Real Website
Most playgrounds keep your code inside their editor — you share a link to their site, with their chrome around your work. OneClickLive runs your code the same way, but Deploy publishes it to its own URL where the page stands on its own. Free plan: 3 simultaneous projects, 7-day URLs. Pro: 25 permanent projects with custom subdomains. Run as much as you like for free; deploy only when you want to share.
Who Uses an HTML Sandbox?
Run what ChatGPT, Claude, or Gemini generated before deciding to keep, edit, or deploy it.
Test a snippet, reproduce a bug, or prototype a component without spinning up a local project.
Try HTML, CSS, and JavaScript live and see results instantly — the fastest way to learn by doing.
Prototype a layout, animation, or interaction and share a working URL instead of a screenshot.
Why OneClickLive as Your HTML Sandbox?
Rendering happens client-side in your browser. Paste and run without an account.
Tailwind, jQuery, Chart.js, GSAP, and any HTTPS-loaded CDN script work — no CORS or mixed-content errors.
Paste a component and the sandbox auto-bundles a React 18 runtime, so JSX runs without a build step.
When it works, one click turns your sandbox into a standalone hosted page anyone can open.
Curly quotes from AI tools that would break a paste are auto-fixed before running.
Code runs client-side and isn't stored unless you deploy. Deployed URLs use random slugs; Pro adds passwords.
FAQ — HTML Sandbox
What is an HTML sandbox?
An HTML sandbox is an online environment where you paste HTML, CSS, and JavaScript and run it live in your browser without installing anything or setting up a server. OneClickLive runs your code instantly in a sandboxed iframe and lets you deploy it to a real URL when you want to share it.
How do I run HTML code online?
Paste your HTML into the sandbox at the top of this page. It runs live in your browser the moment you paste — CSS and JavaScript included. No account or download is needed. Click Deploy to publish it to a shareable URL.
Is there a free HTML playground?
Yes. OneClickLive is a free HTML playground — paste code and run it live with no signup to test. Deploying to a shareable URL has a free tier (3 projects, 7-day links) plus a Pro upgrade for permanent hosting.
Can I run JavaScript and CSS in the sandbox?
Yes. The sandbox runs inline CSS in <style> tags and JavaScript in <script> tags, plus any library loaded from an HTTPS CDN (Tailwind, jQuery, Chart.js, GSAP). It renders over HTTPS, so external resources work without CORS errors.
Does the sandbox support React or JSX?
Yes. Paste a React component and the sandbox auto-detects JSX and bundles a React 18 runtime, so it runs without a build step or Babel setup.
How is this different from CodePen or JSFiddle?
CodePen and JSFiddle keep your code inside their editor and share it as an embed or a link to their site. OneClickLive runs the same code, but Deploy gives you a real standalone website URL (like abc12345.oneclicklive.app) that opens as a normal page — and you don't need an account to run code.
Can I share my HTML sandbox?
Yes. Click Deploy and your sandbox becomes a live URL you can send by email, Slack, or WhatsApp. It opens as a real web page in any browser, not as an embedded editor.
Is my code private?
Running code happens client-side and isn't stored unless you deploy. Deployed URLs are public but use a random, hard-to-guess slug; Pro plans add password protection.
Run Your HTML in the Sandbox Now
Paste your code. See it run live. Deploy to a real URL when it works.
HTML Sandbox →Free · No download · No signup to run · No credit card