HTML Editor
Edit HTML source and see the rendered page update as you type, with a sandboxed preview that blocks scripts and remote resources.
Preview updates as you type. Scripts and remote resources are blocked.
What is the html editor?
An HTML editor lets you write or revise markup and inspect how a browser renders it. This lightweight editor keeps the source and preview side by side, so you can check headings, links, forms and page structure without opening a separate application. It is intended for quick experiments, learning and reviewing snippets rather than replacing a full development environment. Your text stays in the current page unless you choose to copy or download it.
How it works
Type or paste HTML into the source panel and the preview refreshes immediately in an iframe. The iframe uses an empty sandbox, so scripts cannot run or navigate the parent page. A restrictive content security policy also blocks remote resources and form submissions; inline styles and embedded data images are available for local previews. The editor does not validate markup or save drafts automatically. Copy and download actions operate on the source text in your browser.
Worked example
Paste a small document with a heading, a paragraph and a button into the editor. The preview renders those elements as you change their text or add inline styles. Add a script tag and its code remains inactive in the preview; add an image hosted on another site and it will not load because external requests are blocked. When the markup is ready, copy it to your clipboard or download it as an .html file.
Frequently asked questions
Does the preview run JavaScript?
No. The preview iframe is sandboxed without script permission, so JavaScript in the HTML will not execute.
Can the preview load external images, fonts or stylesheets?
No. Its content security policy blocks remote resources and network connections. Inline styles and data images can be used for local experiments.
Is my HTML uploaded or saved?
No. Editing, previewing, copying and downloading happen in your browser. The tool does not upload or automatically save your source.
Can I download my work?
Yes. Choose Download HTML to save the current source as an .html file, or copy the source to your clipboard.
Does the editor check whether my HTML is valid?
No. It displays how the browser interprets your markup but does not run a validator or report conformance errors.
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