Free tool
Free HTML sandbox
Paste HTML, CSS, and JavaScript, press Run, and watch it execute in an isolated preview. No setup, no local server, nothing stored.
Runs entirely in your browser. Nothing you paste is stored until you choose to publish.
What people run here
A safe place to try code you didn’t write yet, or didn’t write at all
Check AI-generated code
ChatGPT or Claude handed you a block of HTML? Run it here before you trust it, and see exactly what it renders and what its scripts do, isolated from everything else.
An HTML and CSS sandbox for layout
Try a grid, an animation, a one-off style fix. The sandbox renders a full document, so what works here works in a real browser tab.
Test JS snippets safely
Event handlers, DOM manipulation, little widgets: scripts execute inside the isolated frame, with no access to your cookies, files, or this page.
sandbox:/index.html
What sandbox:/index.html means, and how to open it
The next step
When the experiment works, ship it as a real page
Turn it into a URL
Convert the working code into a clean, shareable Pagelive link in one step. Free, no signup.
HTML to URL → →Host it properly
Publish with view analytics, version history, and optional passwords: a link that reports back when it’s opened.
Publish HTML → →Grow it into a website
Going past one experiment? Take the same HTML to a full site: your structure, your domain.
HTML to website → →HTML sandbox FAQ
It is a file path inside an AI assistant’s sandbox, the temporary workspace where a tool such as ChatGPT or Claude writes files while it runs code for you. The sandbox:/ part means the file lives in that virtual file system, not on the internet. You can see it inside the chat, but nobody can open it as a web page.
Because it only means something inside the chat that made it. Your browser has no sandbox:/ address to visit, and the AI’s workspace is private and temporary, so outside the chat the link goes nowhere. Copy the HTML into the sandbox above to run it, or publish it with the box on this page to get a real link that opens anywhere.
Yes. Run as much HTML, CSS, and JavaScript as you like. No signup, no limits, nothing to install.
Yes. The sandbox renders a complete HTML document, so markup, inline styles, style blocks, and script tags all execute exactly as a browser would run them.
Your code runs inside an isolated browser frame with a strict sandbox policy: scripts are allowed, but the frame can’t read your cookies, touch your files, navigate this tab, or reach anything outside itself. That isolation is what makes it a safe place to try code.
No. The sandbox runs entirely in your browser. Nothing you paste is sent to or stored on a server. Code only leaves your machine if you choose to publish it as a page.
Publish it as a real link. Anonymous pages stay live for 7 days; claim one free and it stays live as one of your 2 free pages. Published pages are noindex by default; on Solo they can be password-protected and report opens, unique viewers, and time on page.