About the HTML Viewer
A split-pane HTML editor with a live preview that re-renders as you type. Paste a fragment to see how it renders, prototype a layout without creating a project, or check an email template. The preview runs in a sandboxed iframe, which isolates the code you are testing from the rest of the page.
How to use the HTML Viewer
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Write or paste HTML
Enter markup in the left pane. Inline <style> and <script> blocks work, so you can prototype a complete self-contained page.
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Watch the live preview
The right pane re-renders automatically as you type, inside a sandboxed iframe that keeps the tested code isolated.
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Iterate and copy your code
Adjust the markup until it looks right, then copy it with "Copy HTML". The editor does not keep drafts: reloading the page or closing the tab brings back the starting example.
When to use it
Testing a snippet
Check how a piece of markup renders before dropping it into a larger codebase.
Prototyping a layout
Sketch a flexbox or grid arrangement quickly, without scaffolding a project or starting a dev server.
Teaching and learning HTML
Change a tag or an attribute and see the effect immediately, which makes the markup-to-render relationship concrete.
Frequently asked questions
Does the preview run JavaScript?
Yes, inside a sandboxed iframe. The sandbox restricts what the code can reach, so a script in your test markup cannot interfere with the editor itself.
Can I load external CSS or scripts?
External resources referenced by absolute URL generally load, subject to the sandbox restrictions and the remote server CORS policy.
Is my HTML saved or uploaded?
Nothing is uploaded to any server: everything runs in your browser. It is not saved either, so reloading the page brings back the starting example. Copy your markup before closing the tab.
Can I download the result as a file?
Copy the markup from the editor and save it locally as an .html file. The editor itself is intended for fast iteration rather than project file management.
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