Developer Tool
JSON Schema Generator
Transform your example JSON data into a formal JSON Schema. Specifically optimized for AI agents and LLMs requiring strict structured outputs.
Structured Outputs
This tool automatically sets additionalProperties: false and marks all fields as required, which is required for high-reliability features like OpenAI Structured Outputs.
How to use the JSON Schema Generator
JSON Schema is the standard way to describe the exact structure of a JSON object — which fields exist, their types, and which are required. It powers reliable structured outputs and function calling in AI models, plus API validation and documentation. This tool turns a JSON sample into a valid schema instantly, right in your browser.
- 1Paste an example of your JSON data.
- 2The generator infers types, properties, and required fields.
- 3Review the JSON Schema it produces.
- 4Copy it into your AI tool config, API validation, or docs.
Frequently asked questions
What does this generator do?
It analyzes a JSON sample and produces a valid JSON Schema describing its structure — types, properties, and required fields — that you can use for validation, documentation, or AI outputs.
Why use JSON Schema for AI and LLMs?
JSON Schema defines the exact structure you want a model to return, which is how features like structured outputs and tool or function calling enforce reliable, machine-readable responses instead of free-form text.
Is my JSON kept private?
Yes. The schema is generated locally in your browser, so your JSON data is never uploaded or stored anywhere.
Is this tool free?
Yes, the JSON Schema Generator is free to use with no signup.