Schema Validation

Validate your structured data to catch errors before they affect how AI systems understand your content. Invalid schema can lead to missing or incorrect information in AI responses.

In this guide

Schema validation tools and methods
Common schema errors to avoid
Testing in development workflows
Automated validation integration

10 min read Prerequisite: Crawl Testing

Why Validate Structured Data?

Invalid or malformed structured data can cause several problems:

Silent Failures

AI systems may ignore invalid schema entirely without warning you.

Incorrect Data

Malformed schema might be parsed incorrectly, leading to wrong information.

Missing Rich Results

Search engines and AI won't display enhanced results for invalid schema.

Validation Tools

Google Rich Results Test

The most practical tool for testing schema that powers search features:

search.google.com/test/rich-results

• Test by URL or paste code directly
• Shows which rich results your schema enables
• Highlights errors and warnings
• Preview rendered results

Schema.org Validator

Official validator from Schema.org for strict compliance checking:

validator.schema.org

• Validates against full Schema.org specification
• More comprehensive than Google's tool
• Good for catching edge case issues

JSON-LD Playground

Debug JSON-LD structure and expansion:

json-ld.org/playground

• Visualize JSON-LD expansion
• Check @context resolution
• Debug complex nested structures

Common Schema Errors

Missing Required Properties

{
  "@type": "Product"
  // Missing required: name, offers
}

Each schema type has required properties. Check documentation.

Invalid Property Values

{
  "@type": "Product",
  "name": "Widget",
  "offers": {
    "price": "twenty nine"  // Should be number
  }
}

Properties expect specific data types.

Invalid JSON Syntax

{
  "@type": "Product",
  "name": "Widget",  // Trailing comma
}

JSON must be syntactically valid.

Wrong @context

{
  "@context": "http://schema.org",  // Use https
  "@type": "Product"
}

Use https://schema.org for the context.

Command-Line Validation

Validate schema in your development workflow:

# Install schema-dts for TypeScript validation
npm install schema-dts

# Use jq to validate JSON syntax
cat schema.json | jq .

# Extract and validate schema from HTML
curl -s https://yoursite.com | \
  grep -o '<script type="application/ld+json">.*</script>' | \
  sed 's/<[^>]*>//g' | jq .

Automated Testing

Integrate schema validation into your CI/CD pipeline:

// Example: Jest test for schema validation
const { validateSchema } = require('./schema-validator');

describe('Structured Data', () => {
  test('homepage has valid Organization schema', async () => {
    const html = await fetch('http://localhost:3000/').then(r => r.text());
    const schema = extractJsonLd(html);

    expect(schema).toContainEqual(
      expect.objectContaining({
        '@type': 'Organization',
        'name': expect.any(String),
        'url': expect.any(String)
      })
    );
  });

  test('product pages have valid Product schema', async () => {
    const html = await fetch('http://localhost:3000/products/crm').then(r => r.text());
    const schema = extractJsonLd(html);

    const product = schema.find(s => s['@type'] === 'Product');
    expect(product).toBeDefined();
    expect(product.name).toBeDefined();
    expect(product.offers).toBeDefined();
  });
});

Validation Checklist

Before Deploying Schema

□ Valid JSON syntax (no trailing commas, proper quotes)
□ Correct @context (https://schema.org)
□ All required properties present
□ Property values match expected types
□ Passes Google Rich Results Test
□ Schema content matches visible page content
□ No deprecated properties

Key Takeaway

Validate before you deploy.

Invalid structured data is worse than no structured data. It can mislead AI systems or be ignored entirely. Use validation tools in development and automate checks in CI/CD.

Sources

Schema.org Validator: Official validation tool for Schema.org structured data
Google Rich Results Test: Test and validate rich snippets eligibility
JSON-LD Playground: Debug and visualize JSON-LD structure