Free Developer Tool - runs 100% in your browser
HTML Preview
Scroll down to learn more about this tool
Preview HTML live in your browser
This HTML preview tool renders your markup as you type - a zero-setup playground for testing snippets of HTML, CSS and JavaScript without creating a file or spinning up a dev server. Paste an email template, a component snippet from documentation, or generated markup from a CMS and see exactly how a browser displays it.
Sandboxed and safe
The preview runs inside a sandboxed iframe: the rendered page cannot navigate this tab, access your cookies for this site, or reach outside its frame. JavaScript execution is opt-in via the checkbox - untick it to safely inspect markup from untrusted sources with scripts disabled entirely.
What to use it for
- Learning HTML & CSS - instant feedback beats save-and-refresh cycles.
- Email templates - sanity-check table-based layouts and inline styles.
- Debugging generated markup - paste HTML from a CMS, scraper or AI and see what it actually looks like.
- Sharing quick demos - reproduce a layout bug in a few lines before filing an issue.
Your code never leaves the page - rendering happens locally via an iframe srcdoc. If your snippet contains entities like < that should be real tags, decode them first with theHTML entity decoder.