JSON to JSON Schema generator
Paste a JSON sample, such as an API response, and get a JSON Schema that describes it — nested objects, arrays, required fields and common string formats.
Runs in your browser — nothing you paste is sent to a server.
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"type": "object",
"properties": {
"createdAt": {
"type": "string",
"format": "date-time"
},
"email": {
"type": "string",
"format": "email"
},
"id": {
"type": "string",
"format": "uuid"
},
"owner": {
"type": "object",
"properties": {
"age": {
"type": "integer"
},
"name": {
"type": "string"
}
},
"required": [
"age",
"name"
]
},
"tags": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"createdAt",
"email",
"id",
"owner",
"tags"
]
}Draft 2020-12 — the same draft OpenAPI 3.1 uses.
Serve mock responses from this schema →Frequently asked questions
Which JSON Schema draft does it use?
Draft 2020-12. The output declares "$schema": "https://json-schema.org/draft/2020-12/schema", which OpenAPI 3.1 also uses.
How are arrays with different item shapes handled?
Object items are merged into one item schema: a property is listed as required only if every item has it. Items of different types are combined with anyOf.
Can I use the schema for mock responses?
Yes. Add it as a response schema on a request in apikumo and publish the collection: its mock server then returns responses at /mock/<path> built from that schema.
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