How to use: JSON Schema Generator
JSON Schema Generator is a free online JSON Tools tool that infer a JSON Schema 2020-12 document from a sample, detecting dates, emails, URIs and UUIDs instantly in your browser. Paste your data, adjust the options and get the result in real time — no installation, no sign-up, and nothing is ever uploaded to a server.
Use JSON Schema Generator now →
Description
Infer a JSON Schema 2020-12 document from a sample, detecting dates, emails, URIs and UUIDs.
- JSON Tools
- Because everything is computed client-side, JSON Schema Generator is safe to use with sensitive data such as API keys, tokens or private logs.
How to use
Using JSON Schema Generator takes three steps:
- Paste your data into the input box (or load the example).
- Configure the options to match your target format or scenario.
- Copy, download or inspect the output — it updates live as you type.
Run
Examples
A sample instance; the generator infers types, required fields and string formats.
Input
{"id":42,"email":"ada@example.com","created":"2026-09-11","tags":["a","b"],"active":true}
Output
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"type": "object",
"properties": {
"id": {
"type": "integer"
},
"email": {
"type": "string",
"format": "email"
},
"created": {
"type": "string",
"format": "date"
},
"tags": {
"type": "array",
"items": {
"type": "string"
}
},
"active": {
"type": "boolean"
}
},
"required": [
"id",
"email",
"created",
"tags",
"active"
],
"additionalProperties": false
}
This output was produced by actually running the tool, not written by hand.
Use cases
Common situations where JSON Schema Generator helps:
- Infer a JSON Schema 2020-12 document from a sample, detecting dates, emails, URIs and UUIDs.
Parameters
This tool has no options — it works on the input alone.
FAQ
What is JSON Schema Generator?
JSON Schema Generator infer a JSON Schema 2020-12 document from a sample, detecting dates, emails, URIs and UUIDs. It runs entirely in your browser, so your data stays private.
Is JSON Schema Generator free to use?
Yes. JSON Schema Generator is free, unlimited and works without registration or installation.
Does my data get uploaded?
No. All processing happens locally in your browser; nothing is sent to any server.
Good to know
- Everything runs client-side, so extremely large inputs are limited by your browser tab’s memory rather than by a server upload limit.