Detect, validate and remediate structured data site-wide, with source-grounded JSON-LD.
24 active of 24 published rules · each active rule is versioned and backed by evidence. Planned rules are on the roadmap.
The page exposes no JSON-LD structured data.
What it checks
Counts JSON-LD blocks on the page; flags pages with none.
Confidence
High — derived from evidence quality, not asserted.
A JSON-LD block is present but is not valid JSON, so it cannot be read by search engines.
What it checks
Attempts to JSON-decode each JSON-LD block; flags any that fail.
Confidence
High — derived from evidence quality, not asserted.
A structured-data entity omits a property that schema.org marks as required for its type.
What it checks
Parses each entity and checks the required properties for its type (Article headline, Product name, …).
Confidence
High — derived from evidence quality, not asserted.
A schema property holds a value of the wrong data type (e.g. a date field with no valid date).
What it checks
Validates typed properties such as datePublished/dateModified against their expected format.
Confidence
Medium — derived from evidence quality, not asserted.
The schema headline and the visible H1 are too dissimilar, so the structured data may not reflect the page.
What it checks
Compares the schema headline to the H1 text (similarity below 0.6 fails).
Confidence
Medium — derived from evidence quality, not asserted.
The page declares an aggregate rating in schema but no reviews are present — a pattern search engines penalise.
What it checks
Detects AggregateRating with no accompanying Review entity.
Confidence
Medium — derived from evidence quality, not asserted.
A page marked as FAQPage contains fewer than two Question entities — too thin to justify the schema.
What it checks
Counts Question entities in a FAQPage’s mainEntity.
Confidence
High — derived from evidence quality, not asserted.
An FAQ question’s acceptedAnswer is empty or under 20 characters — effectively no real answer.
What it checks
Reads each Question’s acceptedAnswer text length.
Confidence
High — derived from evidence quality, not asserted.
The same schema @id identifies entities of different @type across the site — an internal contradiction.
What it checks
Collects @id → @type across crawled pages and flags any @id with more than one type.
Confidence
High — derived from evidence quality, not asserted.
The page uses an older structured-data format instead of the now-preferred JSON-LD. Informational.
What it checks
Detects Microdata/RDFa markup with no JSON-LD present.
Confidence
High — derived from evidence quality, not asserted.
Organization schema exists but declares no logo — relevant for knowledge-panel eligibility.
What it checks
Checks Organization entities for a logo property.
Confidence
High — derived from evidence quality, not asserted.
A product Offer declares a price but no valid ISO priceCurrency, which can make the listing ineligible for rich results.
What it checks
Checks each Offer with a price for a 3-letter priceCurrency code.
Confidence
High — derived from evidence quality, not asserted.
A Review entity does not specify what is being reviewed.
What it checks
Checks Review entities for an itemReviewed reference.
Confidence
High — derived from evidence quality, not asserted.
Video structured data is missing thumbnailUrl or uploadDate — fields required for rich results.
What it checks
Checks VideoObject entities for thumbnailUrl and uploadDate.
Confidence
High — derived from evidence quality, not asserted.
The position values in a breadcrumb list skip numbers or repeat, breaking the intended ordering.
What it checks
Checks BreadcrumbList item positions are a sequential 1..n.
Confidence
High — derived from evidence quality, not asserted.
A LocalBusiness entity lacks both address and geo-coordinates — critical for local search.
What it checks
Checks LocalBusiness entities for an address or geo property.
Confidence
High — derived from evidence quality, not asserted.
An image referenced in structured data returns an error status when fetched.
What it checks
Fetches image URLs from structured data (SSRF-guarded, capped) and flags 4xx/5xx.
Confidence
High — derived from evidence quality, not asserted.
A product price is declared without an expiration date. Informational — common but not ideal.
What it checks
Checks priced Offers for a priceValidUntil property.
Confidence
High — derived from evidence quality, not asserted.
A structured-data entity omits a property schema.org recommends (but does not require) for its type.
What it checks
Checks each entity against a recommended-property profile for its type (e.g. Article author/image).
Confidence
Medium — derived from evidence quality, not asserted.
A declared @type does not match the bundled schema.org vocabulary — likely a typo or invented type.
What it checks
Compares each top-level @type against the bundled schema.org vocabulary snapshot (v1).
Confidence
Medium — derived from evidence quality, not asserted.
Two entities of the same type and name declare contradictory values (e.g. two Products with different prices).
What it checks
Groups Product/Offer entities by name and flags differing prices.
Confidence
Medium — derived from evidence quality, not asserted.
A breadcrumb item points to a different host than the page, so it does not reflect the site hierarchy.
What it checks
Compares BreadcrumbList item URLs against the page host.
Confidence
Medium — derived from evidence quality, not asserted.
Both WebPage and Article entities are declared without a mainEntityOfPage link, leaving the canonical entity ambiguous.
What it checks
Detects co-present WebPage + Article with no mainEntityOfPage relationship.
Confidence
Medium — derived from evidence quality, not asserted.
The Article datePublished year does not appear anywhere in the visible page text.
What it checks
Compares the schema datePublished year against the visible page text.
Confidence
Low — derived from evidence quality, not asserted.