HTML Viewer and Tester
Paste HTML, CSS and JavaScript and see it render immediately — a scratchpad for testing a snippet without setting up a project.
How to use the HTML Viewer and Tester
- Paste your HTML, including any inline CSS and JavaScript.
- The preview renders immediately.
- Edit and re-run until it behaves the way you want.
About the HTML Viewer and Tester
Sometimes you just want to know whether a snippet works before committing it to a codebase. This runs the code in a sandboxed frame in your browser, so there is nothing to install and nothing to deploy. It is well suited to checking a layout idea, testing a CSS property, or verifying markup you have been sent before pasting it into a real page.
Frequently asked questions
Can I include CSS and JavaScript?
Yes, inline style and script tags run just as they would in a normal page.
Is my code saved or uploaded?
No. It runs locally in a sandboxed frame in your browser.
Can I load external libraries?
Yes, script tags pointing at a public CDN work as long as you are online.
Does it actually execute the code?
Yes. The runner renders your HTML, CSS and JavaScript live in a sandboxed frame, so you see the real result rather than a highlighted listing. Nothing is saved or uploaded — reload the page and it is gone.
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Runs entirely in your browser — nothing you enter is uploaded. Last reviewed and updated .