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Structured DataJune 22, 2026· 9 min read

Schema Markup Validator & Checker: How to Test Your Structured Data (Free)

Schema markup errors are invisible — your page looks fine to visitors but Google can't read your structured data. A schema markup validator catches every error before it costs you rich results.

What is schema markup?

Schema markup is code you add to your webpage that helps Google understand what your content is about. It uses a standardised vocabulary from schema.org — maintained by Google, Microsoft, Yahoo, and Yandex — to describe things like products, articles, events, people, and organisations in a way search engines can read directly.

Without schema markup, Google has to guess what your content means. With schema markup, you tell it directly: "this is a product page, the price is $29, it has 4.8 stars from 312 reviews." That clarity unlocks rich results — the enhanced search listings with star ratings, FAQ dropdowns, prices, and breadcrumbs that get dramatically higher click-through rates.

The most common format for schema markup is JSON-LD (JavaScript Object Notation for Linked Data) — a script tag placed in your page's <head> or <body>. Google recommends JSON-LD because it keeps your structured data separate from your visible content, making it easier to add and maintain.

Quick example: FAQPage schema

Adding FAQPage schema to a page with FAQ content can trigger FAQ rich results in Google Search — expandable question/answer dropdowns directly in the search results. These can double your click-through rate by taking up more space on the page.

Why you need a schema markup checker

Schema markup is easy to write incorrectly. A single missing required property, a mistyped field name, or an invalid data type is enough for Google to ignore your entire schema block — and you'd never know unless you ran a schema markup checker.

Common schema errors that a validator catches:

  • ✗
    Missing required properties: Product schema without a "name" or "offers" block — Google won't show star ratings
  • ✗
    Wrong data types: Putting a string where a number is expected (e.g. "price": "29" instead of "price": 29)
  • ✗
    Invalid @type values: Using "Products" instead of "Product" — schema.org types are case-sensitive
  • ✗
    Broken JSON syntax: A missing comma or bracket makes the entire JSON-LD block unparseable
  • ✗
    Schema not matching page content: Adding 5-star review schema to a page with no visible reviews — Google will ignore it
  • ✗
    Multiple conflicting schemas: Two Product schemas on the same page with different prices — confuses Google

A schema markup validator checks your page for all of these automatically. You don't need to read through your JSON-LD manually or guess why your rich results aren't showing.

How to check your schema markup (step by step)

Using a free schema checker takes less than 30 seconds:

1

Go to the schema markup checker

Open SEO-Snap's free Schema Markup Validator — no account or signup required.

2

Enter your page URL

Paste the full URL of the page you want to check (including https://). This works on any publicly accessible page.

3

Run the check

The tool fetches your page's HTML, finds every JSON-LD block, and validates each one against schema.org standards.

4

Review the results

You'll see a list of schema types found, any errors or warnings, required properties that are missing, and which Google rich results you're eligible for.

5

Fix and recheck

Fix any errors in your schema code, redeploy your page, and run the checker again to confirm everything is valid.

Free Schema Markup Checker & Validator

Check any URL for schema errors, validate JSON-LD, and see which rich results you qualify for — free.

Check Schema Markup Free →

Schema types that unlock Google rich results

Not all schema types get visible rich results in Google Search. These are the most impactful ones to implement and validate:

{}

FAQPage

Example: FAQ section on any page

→ Rich result: Expandable Q&A dropdowns in search results

{}

Product

Example: E-commerce product pages

→ Rich result: Star ratings, price, and availability in search

{}

Article / BlogPosting

Example: Blog posts and news articles

→ Rich result: Article rich snippet with date and author

{}

BreadcrumbList

Example: Any page with a navigation path

→ Rich result: Breadcrumb trail shown below the page title in search

{}

LocalBusiness

Example: Physical stores, restaurants, services

→ Rich result: Business info panel with map, hours, phone

{}

Recipe

Example: Food and cooking pages

→ Rich result: Cook time, calories, and star ratings in search

{}

HowTo

Example: Step-by-step tutorial pages

→ Rich result: Numbered steps shown directly in search results

{}

Review / AggregateRating

Example: Review pages or product pages with ratings

→ Rich result: Star rating and review count in search snippet

⚠ Schema must match your visible page content

Google cross-checks your schema against your visible page content. If your schema says you have 150 reviews but your page shows none, Google will ignore your schema entirely. Always make sure your structured data accurately represents what users can see on the page.

JSON-LD schema markup example

Here's a correct example of FAQPage schema in JSON-LD format — the most commonly added schema type because it directly increases your search result size:

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "What is schema markup?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Schema markup is code added to your webpage
        that helps search engines understand your content
        and display rich results in Google Search."
      }
    },
    {
      "@type": "Question",
      "name": "Does schema markup improve rankings?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Schema markup does not directly improve rankings,
        but it can dramatically improve click-through rates
        by enabling rich results that take up more space
        and look more compelling in search results."
      }
    }
  ]
}
</script>

Add this to your page's <head> section. After adding, run it through a JSON-LD checker to confirm there are no syntax errors before publishing.

Free JSON-LD checker tip

After writing any JSON-LD schema, always validate it with a schema checker before deploying. A single misplaced comma will silently break the entire block and Google won't show any rich results — with no error message to tell you why.

5 schema markup mistakes that block rich results

01

Using the wrong schema type for your content

Using "Article" schema on a product page, or "Product" schema on a blog post. Run a schema markup checker to confirm you're using the right type for your content.

02

Missing the required @context and @type

Every JSON-LD block must start with "@context": "https://schema.org" and "@type". Without these, your schema is invalid and won't be processed.

03

Schema on pages that don't match the schema

Adding Product schema to a category page, or Review schema to a page with no reviews. Google validates schema against visible content — mismatches get ignored.

04

Broken JSON syntax

A missing closing bracket, an extra comma, or unescaped special characters break the entire JSON-LD block. A JSON-LD validator will catch these instantly.

05

Not rechecking after site updates

CMS updates, theme changes, and plugin conflicts can silently remove or break your schema markup. Run a schema checker regularly — not just when you first add it.

Frequently asked questions

What is a schema markup validator?▼
A schema markup validator (also called a schema checker) is a tool that reads the structured data on your webpage and checks it for errors. It verifies your JSON-LD is correctly formatted according to schema.org standards and tells you which Google rich results you qualify for.
Is there a free schema markup checker?▼
Yes — SEO-Snap offers a free schema markup checker that works on any public URL. It extracts all JSON-LD blocks from your page, validates them against schema.org, identifies errors, and shows which rich results you're eligible for. No account required.
What is the difference between a schema validator and Google's Rich Results Test?▼
Google's Rich Results Test checks whether your page is eligible for specific rich result types. A schema markup validator goes further — it validates your JSON-LD syntax, checks all schema types (not just rich-result-eligible ones), identifies missing required properties, and gives you a full structured data audit.
How do I fix schema markup errors?▼
Run your URL through a schema markup checker to see the exact errors. Common fixes: add missing required properties (like "name" on a Product), fix JSON syntax errors (missing commas or brackets), correct @type values (case-sensitive — "FAQPage" not "faqpage"), and make sure your schema matches your visible page content.
Does schema markup directly improve Google rankings?▼
Schema markup is not a direct ranking factor — it does not boost your position in search results on its own. However, rich results from schema markup significantly improve click-through rates, which is a strong engagement signal. More clicks from the same position can indirectly improve rankings over time.
How often should I check my schema markup?▼
Check your schema markup whenever you: update your CMS or theme, install or update plugins, redesign pages, add new content types, or notice a drop in rich results in Google Search Console. Schema can break silently during site updates — regular checks prevent traffic losses you'd never trace back to the cause.

Free Tool

Check your schema markup now — free

Validate your JSON-LD structured data, find errors instantly, and see exactly which Google rich results your pages qualify for. No signup required.

Validate Schema Markup Free →

Works on any public URL · Instant results · No account needed

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