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WordPress fix guide

Missing or Invalid DOCTYPE Declaration on WordPress

No <!DOCTYPE html> found. Without it, browsers render in quirks mode which causes inconsistent styling and layout.

Issue ID: TECH-DOCTYPE-001Severity: moderateEffort: S

Why this matters

No <!DOCTYPE html> found. Without it, browsers render in quirks mode which causes inconsistent styling and layout. This affects crawlability, rendering, and whether the site can be interpreted correctly by search engines.

WordPress fix path

How to fix this on WordPress

Use the page editor, theme, or SEO tooling depending on where this issue lives.

  1. 1Inspect the page and theme output.
  2. 2Apply the fix in the most direct place.
  3. 3Publish and validate with a re-audit.

After you fix it

  • View page source and confirm <!DOCTYPE html> is the first line

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