HTML Validator & Formatter
Use this tool to validate and format your HTML code directly in the browser. Instantly catch common HTML issues like unclosed tags, invalid nesting, duplicate IDs, and deprecated tags, or neatly format your markup for readability.
Free Online HTML Formatter & Validator – Clean Code, Fewer Errors
Welcome to your destination for expert web tools and smart development resources. Our free HTML Formatter and Validator helps developers, designers, and content creators clean up messy HTML, check for HTML errors, and format code for better readability — all from your browser.
Why Use Our HTML Tool?
- Instant HTML validation with checks for unclosed tags, invalid nesting, and deprecated elements
- Clean, indented, and readable HTML formatting in a single click
- Client-side only — no uploads, no servers, no data tracking
- Perfect for SEO professionals, frontend developers, and bloggers
Built for Modern Web Development
Whether you're debugging broken HTML, preparing markup for CMS platforms like WordPress, or optimizing for SEO, our tool is designed to support modern web standards. Easily detect HTML5 issues, avoid accessibility mistakes, and ensure your code is production-ready.
Trending Keywords We Cover:
- Online HTML validator, free HTML formatter, clean HTML tool
- HTML5 checker, SEO-friendly markup, web dev utilities
- HTML code beautifier, W3C HTML validator alternative
- Developer productivity tools, no-login HTML cleanup
From learning HTML basics to auditing complex code, AllThingsWeb makes it easy, fast, and accessible. Discover more web development tools, generative AI resources, and trending tech insights in our Explore Topics and Newsroom sections.
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