JSON-LD checks

Testomato can monitor structured data values embedded in <script type="application/ld+json"> blocks on any page. Select a preset check from the rule picker, then provide an assertion value; Testomato extracts the matching property and applies a string operator against it.

Rule syntax

Preset checks use the prefix JSON-LD: followed by either a type scoped path or a bare property path.

Rule	What it targets
JSON-LD: name	name in any JSON-LD block on the page
JSON-LD: AR.ratingValue	nested property, no type filter
JSON-LD: Product: name	only blocks where @type is Product
JSON-LD: @type	the type field itself
JSON-LD: Product: offers.price	deeply nested, type-scoped

Type scoping: if the first path segment starts with an uppercase letter, it is treated as a @type filter. For example, JSON-LD: Product: name only checks blocks where the @type is Product — all other blocks are ignored. Lowercase-first paths (like JSON-LD: name) check all blocks on the page.

Testomato handles multiple <script type="application/ld+json"> blocks per page, @graph containers, and top-level JSON arrays automatically.

Note

JSON-LD checks work with any vocabulary, not just schema.org. The checker never reads @context — it treats every block as plain JSON and extracts values by key name. Custom or mixed vocabularies work the same way.

Operators

JSON-LD checks support the same operators as other string checks.

Tip

For dynamic values — ratings, prices, dates — use matches with a regex pattern instead of equals. JSON-LD: AR.ratingValue matching \d+(\.\d+)? passes for any numeric rating regardless of the current value.

Pages with multiple JSON-LD blocks

Many pages include more than one JSON-LD block. Testomato extracts the target property from every block on the page and tests the operator against each value. The check passes if any single value matches (it short-circuits on the first match).

For example, a homepage with three blocks (WebSite, WebApplication, Organization) all carrying a name property:

Check	WebSite	WebApplication	Organization
JSON-LD: name contains Testomato	Testomato ✓	Testomato	Testomato s.r.o.
JSON-LD: name contains Testomato s.r.o.	Testomato	Testomato	Testomato s.r.o. ✓
JSON-LD: AR.ratingValue matches \d+	—	4.6 ✓	—

If you need to target a specific block, use the type-scoped form. JSON-LD: Organization: name only checks blocks where @type is Organization.

Caution

Negated operators (does not contain, does not match) also pass if any single extracted value satisfies them. On a page with multiple blocks, JSON-LD: name does not contain foo passes as long as one block's name doesn't contain foo — even if another block's does. Use type-scoped checks to avoid ambiguity.

Failure modes

What happened	Error shown
No <script type="application/ld+json"> blocks found, or all blocks are empty	Missing JSON-LD
At least one block contains malformed JSON and no valid block remains	Invalid JSON-LD
Block found, but the property path is not present	Missing JSON-LD property: {path}
Property found, but value fails the operator	Check marked failed, no message

Exact type matching

The @type filter matches the block's declared type exactly. A page using @type: BlogPosting will not match JSON-LD: Article: headline, even though BlogPosting is a subtype of Article in schema.org.

Starter checks

The rule picker includes pre-built presets for the most common fields.

Presence and type

Check	Operator	What it catches
JSON-LD: @type	matches [A-Z]\w+	At least one JSON-LD block exists with a valid type

Product

Check	Operator	What it catches
JSON-LD: Product: name	matches .*	Product name is present
JSON-LD: Product: offers.price	matches .*	Price is populated
JSON-LD: AR.ratingValue	matches \d+(\.\d+)?	Rating is a valid number

Article

Check	Operator	What it catches
JSON-LD: Article: headline	matches .*	Headline is present
JSON-LD: Article: datePublished	matches \d{4}-\d{2}-\d{2}	Published date is a valid ISO date
JSON-LD: author.name	matches .*	Author name is populated

Organization

Check	Operator	What it catches
JSON-LD: Organization: name	matches .*	Organization block has a name

Breadcrumbs

Check	Operator	What it catches
JSON-LD: BreadcrumbList: itemListElement	contains Home	Breadcrumb items include a home entry

Resources

• Monitoring JSON-LD Structured Data — background, examples, and what to monitor first
• Google Rich Results Test — check eligibility for rich results
• Schema.org Validator — validate structured data against the schema.org vocabulary
• JSON-LD Playground — experiment with JSON-LD syntax interactively
• schema.org — type and property reference