toJsonLd

Serialize one schema or an array of schemas into a script-safe JSON-LD string.

const toJsonLd = (schema: StructuredDataSchema | StructuredDataSchema[]) => string;

Behavior

A single schema is spread into the context object:

toJsonLd(createPersonSchema({ name: "Ada" }));
// {"@context":"https://schema.org/","@type":"Person","name":"Ada"}

An array becomes a @graph:

toJsonLd([website, person]);
// {"@context":"https://schema.org/","@graph":[{...},{...}]}

The @context is always https://schema.org/.

Escaping

Applied after JSON.stringify, so the output is still valid JSON that parses back to the input:

Character	Emitted	Why
`<`	`\u003c`	`</script>` inside a value would end the script element
`>`	`\u003e`	Defense in depth alongside `<`
`&`	`\u0026`	Prevents entity interpretation in non-script contexts
U+2028	`\u2028`	Legal in JSON, breaks legacy JavaScript string contexts
U+2029	`\u2029`	Same as U+2028

Failure mode

If the schema can’t be stringified (for example, a circular reference), toJsonLd logs the error with console.error and returns "{}" — a harmless empty object, so a bad node degrades to “no structured data” instead of broken markup or a crashed render.

const person = createPersonSchema({ name: "Ada" });
person.mainEntityOfPage = person as never; // cycle
toJsonLd(person); // "{}" (and one console.error)