Free Schema Validator: Check JSON-LD and Structured Data

What is a schema validator?

A schema validator is a tool that checks structured data (JSON-LD, Microdata or RDFa) for three things: whether the code parses, whether every type and property exists in the schema.org vocabulary, and whether the markup includes the properties Google requires for a rich result. Invalid schema causes no visible error on a page, so search engines simply ignore it. Validating before you publish, and again after any template change, is the only way to catch that silent failure. This schema checker reads the current schema.org release (939 types, 1,538 properties) and Google’s documented requirements for 18 rich result types.

Price

Free, unlimited

Formats

JSON-LD, Microdata (RDFa is detected, not checked)

Checks

Syntax, schema.org vocabulary, Google required and recommended fields

Privacy

Pasted code never leaves your browser

How to use the schema validator

1. Paste or point. Paste a JSON-LD block, paste a whole page’s HTML, or switch to Check a URL and enter a live page address. The URL check fetches the page once through this site and reads its markup in your browser.
2. Validate. Press Validate code (or Ctrl+Enter). Each block of structured data on the page gets its own report, with errors first, then warnings, then notes.
3. Read the eligibility line. Under each block you’ll see whether it passes Google’s required-property checks for its rich result type, for example “Product snippet: missing offers”.
4. Fix and re-check. Every message names the exact path (such as offers.price) and links to the matching Google or schema.org documentation. If the code came from a form, regenerate it with the Schema Markup Generator rather than hand-editing brackets.
5. Confirm in Google. Use the Open Google Rich Results Test button for Google’s own verdict on a live URL. Google’s tool is the final word on eligibility; this validator is for catching problems quickly while you work.

What this schema checker tests

One thing no validator can check is whether the markup matches what visitors see on the page. Google’s structured data policies require that, and marking up content that isn’t visible can cost you rich results across the whole site.

Schema validator vs Google Rich Results Test vs validator.schema.org

The three tools answer different questions, so most people use two of them. This page is built for the editing loop; Google’s tester is the final check.

Our guide to testing structured data before you publish walks through a full pre-launch check with all three.

Common schema errors this validator finds

• Missing required field, usually offers, image, startDate or address. Add the property with a real value from the page.
• Price with a currency symbol ("$19.99"). Google wants a bare number plus priceCurrency.
• Rating without a count. AggregateRating needs ratingCount or reviewCount as well as ratingValue.
• Dates in local formats such as 10/08/2026. Use ISO 8601: 2026-10-08 or 2026-10-08T09:00:00+05:00.
• Relative image URLs (/img/a.jpg). Google needs full https:// URLs it can crawl.
• Capitalisation slips: localbusiness, DatePublished, Instock. Types are PascalCase, properties camelCase, enumeration values full schema.org URLs.
• Property on the wrong type, for example datePublished on a Product. Schema.org defines it for CreativeWork; Google ignores it there.
• Trailing commas left behind after deleting a line. JSON has no tolerance for them.

Need the markup rebuilt instead of patched? The generator produces valid JSON-LD for Local Business, Organization, Article, FAQ, Product, Review, Event and Breadcrumb pages, and our FAQ schema guide explains why Google retired FAQ rich results in May 2026 and what Q&A markup still does.

Frequently asked questions

Is this schema validator free?

Yes, with no limits and no account. The URL check is rate-limited to 30 fetches per 10 minutes per connection to keep the service available for everyone; pasted code has no limit.

Does a clean result mean I’ll get a rich result?

No. A clean result means the markup is valid and includes everything Google documents as required. Google still decides case by case, and also checks that the markup matches the visible page. Use the Rich Results Test button for Google’s own eligibility verdict.

Can it check Microdata and RDFa?

Microdata, yes: paste the HTML or use the URL check and each itemscope becomes its own report. RDFa is detected and reported but not validated. JSON-LD is the format Google recommends, and the generator can rebuild your markup in it.

Why does my code pass here but fail in Google’s tool?

Usually because the live page differs from the code you pasted: a plugin changes the output, JavaScript injects the markup after load, or the page is blocked from crawling. Run the URL check here first, then the Rich Results Test on the same URL.

What happens to the code or URL I enter?

Pasted code is parsed in your browser and never sent to our server. A URL is fetched once by our server so your browser can read the HTML, and nothing is stored. Your last input is kept in your browser’s local storage so you can come back to it, and Clear removes it.

How current is the schema.org vocabulary?

The vocabulary file is generated from schema.org’s current release and includes the full list of types, properties, enumeration values and superseded terms, so new types appear here as soon as we rebuild the file.