Catch parse problems
Run a server-side HTML parse check and review warnings before the page becomes a release.
Formatters
Validate HTML parse errors
Run a server-side HTML parse check and return actionable errors or warnings for static page documents.
Processed on the server.
Do not paste passwords, tokens, or private keys.
Results will appear below the editor after you run the tool.
Useful for generated pages
AI and builder exports can contain subtle nesting or document structure issues.
Better deploy confidence
Validation reduces avoidable release mistakes before you publish.
How to use HTML Validator
Validate HTML structure before a generated or edited page becomes a production deployment.
Paste the page
Use the complete HTML document when possible, not just one section.
Run validation
StaticX checks server-side parse results and reports problems.
Fix and retest
Correct the markup, test again, then publish when the page is clean.
Browsers forgive invalid HTML, but production teams should not rely on that.
A page may appear to work while still having broken structure, missing metadata, or form fields outside the expected context.
Validation is especially important before an AI agent deploys a site because it creates a concrete checkpoint before production.
Validation before publishing
Checks structure
Use it to catch malformed tags, nesting problems, and document issues.
Complements preview
A visual preview can miss semantic or metadata problems.
Good before versions
Validate before creating an immutable deployment version.
Questions about HTML Validator
Short, practical answers for using this page safely.
Does valid HTML guarantee perfect design?
No. It confirms structure, not visual quality. Preview and QA are still needed.
Should every deployment be validated?
For agent and CI workflows, yes. Validate index.html and 404.html before deploy.
Can the validator fix my HTML?
No. It reports issues so you or an agent can correct them deliberately.