What is HTML Viewer?
HTML Viewer is a free browser-based workspace for writing, editing and previewing HTML, CSS and JavaScript. Simple mode keeps one complete document on the shortest possible update path, making it useful for code snippets, lessons, component experiments and fast bug reproductions. Files mode preserves folders and separate source files so stylesheets, scripts, images, fonts and nested pages behave more like a static project opened from a real web root. The editor includes responsive viewport controls, full-page preview, syntax highlighting and several export choices. User-written code is processed locally in the browser rather than stored as a hosted project, while optional analytics and externally hosted website resources are documented separately. No account or paid plan is required. HTML Viewer is intended for learners, designers and developers who need quick visual feedback without setting up a build tool, while still making clear that server routes, framework compilation and backend APIs require their actual runtime.
This workflow provides 2 editing modes, 3 responsive viewport presets and 4 export paths for browser-ready static projects.
The June 2026 release publishes 10 canonical pages, combines 15 source modules in one browser bundle and uses 44-pixel primary mobile targets.
Maintained by HTML Viewer · Updated June 21, 2026.
Core workflows
- Live single-document HTML, CSS and JavaScript preview.
- Multi-file projects with folders and local assets.
- Desktop, tablet and mobile viewport checks.
- HTML, ZIP, local-folder and unified HTML export.