Do your pages embed semantic markup directly in the HTML as a fallback?
Checks for older but still-valid inline metadata formats that some AI crawlers prefer to read.
What this signal tests
We check whether your pages use one of two older standards, called microdata and RDFa, to tag elements inside the HTML with Schema.org meaning. These are inline alternatives to the newer JSON-LD format. They write the semantic information directly onto your visible markup rather than in a separate script block.
Why it matters for your visibility in AI
Most modern AI crawlers prefer JSON-LD, but a meaningful minority still read inline microdata or RDFa first. If your site already uses one of these formats, the signal passes and you gain redundancy: more AI tools can extract structured meaning from your pages without you needing to change anything. If your site has neither inline markup nor JSON-LD, AI tools fall back to reading raw HTML and guessing. That guessing is what causes hallucinated quotes, missing prices, and incorrect attributions in AI search results. You only need one of the three encodings to pass, and JSON-LD is usually the easiest to add.
Pass criteria at a glance
| Criterion | Passes when |
|---|---|
| Microdata or RDFa present, OR JSON-LD present (encodings are alternatives). |
How we test it
We scan your HTML for the telltale attributes used by each format: itemscope and itemtype for microdata, and vocab and typeof for RDFa. If we find them, we confirm the type they reference is a real Schema.org class such as Article or Product. If you have JSON-LD instead, this signal also passes, because all three formats serve the same purpose.
Show technical detection method
Search DOM for itemscope+itemtype OR typeof attributes; require value resolves to Schema.org class.
If your site fails: how to fix it
- If you already have JSON-LD, this signal will pass automatically. No additional work is needed and JSON-LD is the recommended path.
- If your site uses an older theme or plugin that adds microdata or RDFa, verify the itemtype or vocab attributes point to https://schema.org and not a deprecated URL such as data-vocabulary.org.
- If you are starting fresh, choose JSON-LD over microdata or RDFa. JSON-LD is easier to maintain, does not clutter your HTML, and is Google's stated preference.
- Run the Schema.org validator on a sample page to confirm that whatever inline markup you have is correctly recognised.
Quick facts
| Maturity | ESTABLISHED |
|---|---|
| Weight | low |
| Category | Structured Data |
Primary sources
Related signals
Frequently asked questions
Should I use microdata, RDFa, or JSON-LD?
Use JSON-LD. It is what Google recommends, what most AI tools read first, and it keeps your HTML clean because the metadata sits in its own script block. Microdata and RDFa are still valid but harder to maintain and less commonly consumed by newer AI tools.
Do I need to remove old microdata if I add JSON-LD?
No. Multiple encodings on the same page is fine. Some platforms ship microdata by default and adding JSON-LD on top is harmless. If you do remove the old markup, validate that nothing else on your site relied on those classes or attributes for styling or behaviour.
My theme uses microdata but the itemtype points to data-vocabulary.org. Is that a problem?
Yes. data-vocabulary.org was deprecated in 2020 and is no longer recognised by Google or most AI tools. Update the itemtype attributes to point to https://schema.org, or replace the inline markup with JSON-LD entirely.
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