Comment utiliser : JSON to JSON Schema
- Paste a JSON example — an API response, a config file, a database record — or click Sample.
- For better results paste several examples as a JSON array: fields missing from some become optional, and different types become a union.
- Choose the draft, how required is decided, and whether to detect formats, build enums, forbid extra properties or keep examples.
- Copy or download the schema — or send it straight to the JSON Schema to TypeScript converter or the validator.
How the schema is inferred
- Types: strings, numbers, integers (whole numbers), booleans, null, objects and arrays. A field that is sometimes a number and sometimes null becomes
"type": ["number", "null"]. - Arrays: every item is merged into one
itemsschema, so an array of user objects gets one user schema with all keys seen. - Required: by default a key is required only if it appears in every object of that shape. With one example, all keys are required.
- Formats: strings that all look like an email, URI, UUID, date, date-time, time, IPv4 or IPv6 get a
format. - Enums: a string field with a few repeating values across many examples (like
status) becomes anenum.
An inferred schema describes your examples, not your intent — review it: tighten strings with minLength or pattern, add minimum/maximum to numbers and decide which fields are truly optional. Then check data against it with the JSON Schema Validator or generate types with JSON Schema to TypeScript.
Aussi recherché comme : json schema generator, generate json schema from json, infer json schema, json schema from example, create json schema online, json schema draft 2020-12, json to schema.
Outils complémentaires : JSON to JSON Schema
- JSON to TypeScript — Paste a JSON sample — an API response, a config — and get ready-to-use TypeScript interfaces with nested types, optional properties and union types.
- Formateur JSON — Collez votre code JSON pour le formater, le compresser ou le valider.
- OpenAPI / Swagger Validator — Paste an API specification to check it against the official OpenAPI schema, catch broken references and inconsistent path parameters, and see every endpoint at a glance.
- Générateur de données factices — Créez jusqu'à 10 000 lignes de données de test réalistes — utilisateurs, produits, commandes, adresses, entreprises ou enregistrements API imbriqués — ou élaborez votre propre schéma.
Questions fréquentes
How do I generate a JSON Schema from JSON?
Paste the JSON here: the generator walks every value, writes the matching type, properties and items, marks keys as required and detects formats. Paste several examples in an array for a more accurate result.
Which JSON Schema draft should I use?
Draft 2020-12 is the current version and what OpenAPI 3.1 uses. Choose draft-07 for older tools and libraries that don’t support 2020-12 yet.
Why is a field not marked as required?
It was missing from at least one of your examples. Change “Required fields” to “Every key” if every field must always be present.
Can I turn the schema into TypeScript types?
Yes — click To TypeScript to open the schema in the JSON Schema to TypeScript converter.
Puis-je installer JSON to JSON Schema en tant qu’application web et l’utiliser hors ligne ?
Oui. JSON to JSON Schema est une application web installable (PWA) : elle s’installe depuis votre navigateur, sans passer par une boutique d’applications. Cliquez sur « Installer l’application » en haut de cette page dans Chrome ou Edge (Windows, macOS, Linux, ChromeOS) ; sur Android, utilisez « Partager » → « Ajouter à l’écran d’accueil » sur iPhone et iPad ; ou « Fichier » → « Ajouter au Dock » dans Safari 17+ sur Mac. L’application s’ouvre alors dans sa propre fenêtre avec sa propre icône, et comme elle s’exécute entièrement dans votre navigateur, elle continue de fonctionner hors ligne. Firefox sur ordinateur de bureau ne permet pas d’installer d’applications web. Comment fonctionne l’installation.