Plain JSON is just labelled values — two systems can both write a `material` field and mean different things. JSON-LD adds a `@context` that maps each field to a globally unique URI (a vocabulary term), so the data is self-describing Linked Data: a reader anywhere on the web can resolve exactly what each property means without a private agreement.
For a Digital Product Passport this is what makes the data portable across the EU ecosystem — regulators, recyclers, retailers and AI search engines read the same semantics. TracePass serves every passport as JSON-LD over content negotiation, the machine-readable counterpart to the human-readable QR landing page.
Frequently asked
How is JSON-LD different from plain JSON?
Syntactically a JSON-LD document is valid JSON, so any JSON parser reads it. The difference is the `@context`, which links each field to a shared, web-resolvable definition — turning loose key/value pairs into Linked Data whose meaning is unambiguous across systems.
Why does a Digital Product Passport use JSON-LD?
ESPR requires passport data to be machine-readable and interoperable. JSON-LD gives every field a shared meaning so EU registries, recyclers and AI agents can consume a passport without bespoke integration — and it's the same format GS1's EPCIS 2.0 and Schema.org use.