30 checks in Technical Foundation & Rendering. Automated Its subsection has a live automated checker in the engine.
| ID | Check | Passes when |
|---|---|---|
| 1.8.01 | Validate <!DOCTYPE html> present as first line | Present |
| 1.8.02 | Validate <html lang=""> attribute present and correct | Valid language code |
| 1.8.03 | Validate <meta charset="UTF-8"> present in <head> | Present |
| 1.8.04 | Validate charset declaration is within first 1024 bytes | Early position |
| 1.8.05 | Validate single <html> element wraps entire document | Valid |
| 1.8.06 | Validate single <head> element present | Valid |
| 1.8.07 | Validate single <body> element present | Valid |
| 1.8.08 | Validate no content appears before <head> or between </head> and <body> | Clean structure |
| 1.8.09 | Validate <title> tag present and non-empty | Present |
| 1.8.10 | Validate <title> length 30-60 characters | Optimal range |
| 1.8.11 | Validate <meta name="description"> present | Present |
| 1.8.12 | Validate meta description length 120-160 characters | Optimal range |
| 1.8.13 | Validate exactly one <h1> per page | Single H1 |
| 1.8.14 | Validate heading hierarchy is sequential (no skipped levels) | Sequential |
| 1.8.15 | Validate no unclosed HTML tags | Clean |
| 1.8.16 | Validate no duplicate ID attributes | Unique IDs |
| 1.8.17 | Validate all <img> tags have alt attributes | Present |
| 1.8.18 | Validate all <a> tags have href attributes | Valid |
| 1.8.19 | Validate no deprecated HTML elements (e.g., <font>, <center>, <marquee>) | None |
| 1.8.20 | Validate no deprecated HTML attributes | None |
| 1.8.21 | Validate semantic HTML5 elements used (<main>, <article>, <section>, <nav>, <aside>) | Present |
| 1.8.22 | Validate <main> element used exactly once | Single main |
| 1.8.23 | Validate <nav> element present for primary navigation | Present |
| 1.8.24 | Validate <footer> element present | Present |
| 1.8.25 | Validate no inline styles (style attribute) on critical elements | Minimized |
| 1.8.26 | Validate no inline event handlers (onclick, onload, etc.) | None |
| 1.8.27 | Validate W3C HTML validation passes with zero errors | Zero errors |
| 1.8.28 | Validate Open Graph meta tags present (og:title, og:description, og:image) | Present |
| 1.8.29 | Validate Twitter Card meta tags present | Present |
| 1.8.30 | Compute HTML Structure Integrity Score | Finalized |
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