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ValidateHTML — Startup Profile
Startup

ValidateHTML

Validate HTML, CSS, JSON, XML & more — instantly

Development & IT

About the startup

The problem: web validators are scattered. The W3C validator is slow and clunky. JSONLint only does JSON. CSS Lint is dead. Most tools look like they were built in 2003. ValidateHTML brings 13 essential validation and formatting tools into one clean, fast, free site — no account, no paywall, no rate limits. --- **Tools included** Validators: - HTML Validator (standards compliance + common errors) - HTML5 Validator - CSS Validator - JSON Validator - XML Validator - Open Graph tag checker - Meta tags analyzer - robots.txt validator - Accessibility checker - Page size analyzer Formatters: - HTML Formatter (beautify / minify) - JSON Formatter (pretty-print / compact) --- **Key features** - Quality Score 0–100 + Grade A–F on every tool - PDF export for every validation report - Paste code or enter a URL — your choice - Dark UI, fully responsive - No signup, no login, no limits --- **Why it's different** Faster and cleaner than the official W3C validator. More tools than any single-purpose validator. Consistent UX and scoring system across all 13 tools. Built with Next.js on Vercel — it's fast. Built for developers who want to ship clean, accessible, standards-compliant code without slowing down. --- Stack: Next.js · TypeScript · Tailwind CSS · Vercel

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