The two free schema validators worth using are the Schema Markup Validator from schema.org and Google’s Rich Results Test. The first checks whether your markup is valid schema.org of any type. The second checks whether it qualifies for the rich results Google still shows. Run both, fix syntax errors and missing required properties before anything else, then watch the rich result reports in Search Console so a template change doesn’t quietly break things later.
That’s the whole workflow. The rest of this guide covers which tool answers which question, how to read the results, and the errors that do the most damage. Last checked: October 29, 2026.
Which Schema Validator Should You Use?
Each tool answers a different question, so the right one depends on what you need to know.
| Tool | What it checks | Use it when |
|---|---|---|
| Schema Markup Validator | Whether your JSON-LD, Microdata or RDFa is valid against the full schema.org vocabulary | You want a general structured data checker for any type, including types Google ignores |
| Rich Results Test | Whether markup on a URL or code snippet is eligible for Google rich results, with a preview for some features | You care about how a page can appear in Google Search |
| Search Console URL Inspection | Whether Google found structured data on the live, indexed version of a page | You’ve deployed and want to confirm what Googlebot saw |
| Search Console rich result reports | Valid and invalid items across your whole site over time | You want to catch errors after templates or plugins change |
The Schema Markup Validator replaced Google’s old Structured Data Testing Tool for general validation. It’s the better schema markup checker when you’re using types like Organization details, Person or Service that don’t map to a specific Google feature. The Rich Results Test only reports on types Google supports for rich results, so a perfectly valid Service block can look like “nothing detected” there.
Google’s own guidance draws the line clearly: its structured data introduction tells you to rely on Search Central documentation, not schema.org, as definitive for Google Search behavior. Valid on schema.org doesn’t automatically mean eligible in Google.
How to Test Structured Data, Step by Step
1. Test the live URL in the Schema Markup Validator
Paste the page URL into validator.schema.org and run it. You’ll see every item detected on the page, grouped by type, with errors and warnings beside each property. If you’re working on a staging site that isn’t public, paste the code snippet instead.
Look at the list of detected types first. Duplicate Organization or WebSite blocks are common when a theme and an SEO plugin both output markup, and they’re easy to miss if you only look at error counts.
2. Run the same URL through the Rich Results Test
The Rich Results Test fetches the page as Googlebot, renders JavaScript and lists the rich result types it detected, such as Product, Article, Breadcrumb or Review snippet. Each item is marked valid, valid with warnings or invalid.
Rendering matters here. If your markup is injected by JavaScript (common with tag managers and some headless builds), this test shows whether Google can actually see it after rendering.
3. Check the indexed version with URL Inspection
After deploying, open Search Console and inspect the URL to confirm Google found your structured data on the indexed page. Google’s guidelines name the Rich Results Test and URL Inspection as the two tools that catch most technical errors. The live test reflects what Googlebot gets right now, which can differ from what you see in a browser if caching, geo-redirects or bot rules are involved.
4. Monitor the rich result reports
Search Console groups structured data issues by type across the site. Google suggests using the Rich Results Test during development and these status reports after deployment, because pages “might break after deployment due to templating or serving issues.” A plugin update that drops a required field shows up here as a jump in invalid items.
The Structured Data Errors to Fix First
Not every warning deserves your time. Here’s the order that usually matters, starting with the errors that stop markup from working at all.
1. Syntax errors (unparsable structured data)
A missing comma, an unclosed bracket or a stray quote makes the entire JSON-LD block unreadable. Both validators will flag it, and Search Console has an “Unparsable structured data” report for exactly this. Fix these first, because nothing else in the block counts until the syntax is valid.
Common causes are hand-edited code in a custom HTML block, smart quotes pasted from a word processor, and template variables that output an unescaped quote mark from a product name.
2. Missing required properties
Google’s structured data guidelines say items “that are missing required properties are not eligible for rich results.” The Rich Results Test lists these as errors, for example a Product without name or a review snippet without the item being reviewed. Each feature’s documentation page lists what’s required.
3. Invalid property values
The property exists, but the value is the wrong type or format. Typical examples:
- Dates that aren’t in ISO 8601 format (use
2026-10-29, notOct 29, 2026). - Prices with currency symbols in the
pricefield instead of a separatepriceCurrency. - Text where a URL or a nested object is expected, such as an
authorgiven as a string when you meant aPerson. - Enumerations that aren’t standard schema.org values. Google has clarified, for example, that local business opening hours must use the standard English schema.org values.
4. Markup that doesn’t match the page
This one passes every validator and still causes trouble. Google’s guidelines say not to “mark up content that is not visible to readers of the page,” and violations can lead to a structured data manual action. A manual action removes rich result eligibility but, per Google, doesn’t affect how the page ranks in web search.
Typical problems: review ratings in markup that don’t appear on the page, prices in schema that differ from the visible price, and FAQ markup for questions that aren’t on the page.
5. Duplicate or conflicting items
Two plugins outputting two different Organization blocks with different logos, or a page that marks up the same product twice with different prices, sends mixed signals. Google’s review snippet documentation was updated in November 2025 to tell site owners to avoid using multiple ways of indicating what’s being reviewed. Pick one source of truth for each entity and remove the rest.
6. Markup for features Google no longer shows
Google has been retiring rich result types. Its documentation updates log records that FAQ rich results stopped appearing in Google Search starting May 7, 2026, and earlier removals include How-to, practice problem, course info, estimated salary, learning video, special announcement and vehicle listing. Markup for these types isn’t an error, and the Schema Markup Validator will still validate it. Just don’t spend time chasing Rich Results Test eligibility for a feature that no longer exists. Our guide to FAQ schema covers whether it’s still worth keeping.
Warnings can usually wait
Warnings flag missing recommended properties. Google’s guidelines say more recommended properties can make an enhanced result more likely, but that it’s more important to supply “fewer but complete and accurate” recommended properties than every possible one with less complete data. Fix errors first, then add the recommended fields that you can fill accurately.
Does Valid Schema Help in AI Search?
Indirectly. Google’s AI features documentation says there’s “no special schema.org structured data” you need to add to appear in AI Overviews or AI Mode. It does list making sure your structured data matches the visible text on the page among its best practices.
Microsoft is more enthusiastic. Its October 2025 guidance on optimizing content for AI search answers describes schema as code that helps search engines and AI systems understand your content, and recommends it alongside clear headings and snippable Q&A, lists and tables.
So treat valid, accurate markup as part of making your pages machine-readable, not as a ranking trick. It only helps if AI crawlers can reach the page in the first place, which is a robots.txt question. Our AI crawler list shows which user agents to allow.
Frequently Asked Questions
What is the best schema validator?
Use the Schema Markup Validator at validator.schema.org for general schema.org validation and Google’s Rich Results Test for Google rich result eligibility. They’re both free, and they answer different questions, so most sites need both.
Is the Google Structured Data Testing Tool still available?
No. Google retired it and its general validation moved to schema.org as the Schema Markup Validator. For Google-specific checks, use the Rich Results Test.
Why does the Rich Results Test say no items detected?
Either the page has no markup Google can see after rendering, or the markup uses types Google doesn’t support for rich results, such as Service. Check the same URL in the Schema Markup Validator. If it finds items there, your markup exists but doesn’t map to a Google feature.
Do warnings in the Rich Results Test hurt my rankings?
No. Warnings mean optional recommended properties are missing. The item can still be eligible. Errors on required properties are what block eligibility.
Can valid structured data still fail to show rich results?
Yes. Google’s guidelines say it doesn’t guarantee structured data will show up even when the Rich Results Test marks it valid, because the algorithm decides what’s best for each search.
How often should I test structured data?
Test when you launch or change a template, and after plugin or theme updates. Between changes, the rich result reports in Search Console catch site-wide breakage.
Which format should I use: JSON-LD, Microdata or RDFa?
Google supports all three and recommends JSON-LD. It’s the easiest to maintain because it sits in one script block instead of being spread through your HTML.
Can AI engines read your site?
Check any page for free: crawler access for ChatGPT, Perplexity, Claude and Google AI Overviews, plus the fixes that matter most.
