> ## Documentation Index
> Fetch the complete documentation index at: https://wiki.platelunchcollective.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Markup Validation

> Markup validation is the process of testing structured data implementation using tools like Google's Rich Results Test and Schema.

*Technical implementation* · *Technical SEO*

## Definition

Markup validation is the process of testing structured data implementation using tools like Google's Rich Results Test and Schema.org validator to confirm it is correctly formatted, error-free, and eligible for rich results. Validation identifies missing required properties, incorrect types, and syntax errors.

## Why It Matters for AI Search

Invalid structured data provides no entity signal benefit. Schema markup with errors may be partially parsed — or ignored entirely — by AI crawlers. Markup validation is the quality control step that ensures schema implementation is actually communicating the intended entity information. For brands implementing Organization schema, LocalBusiness schema, or FAQ schema, validation before deployment prevents silent failures where schema exists in the HTML but is not being processed.

## Related Terms

<CardGroup cols={2}>
  <Card title="Schema markup" href="/ai-search-glossary/schema-markup" />

  <Card title="Rich Results Test" href="/ai-search-glossary/rich-results-test" />

  <Card title="Structured data" href="/ai-search-glossary/structured-data" />

  <Card title="JSON-LD" href="/ai-search-glossary/json-ld" />

  <Card title="Rich result" href="/ai-search-glossary/rich-result" />
</CardGroup>

## Relevant Plate Lunch Collective Services

[AI SEO](https://www.platelunchcollective.com/services/ai-seo)  [Entity SEO](https://www.platelunchcollective.com/services/entity-seo)