JSON Schema Generator
Paste sample JSON and instantly generate a valid JSON Schema (Draft 7). Auto-detects types, required fields, nested objects, and arrays. Free, no sign-up.
Ctrl+Enter to generate
Your JSON stays entirely in your browser. No data is sent to any server.
What is JSON Schema?
JSON Schema is a vocabulary that allows you to annotate and validate JSON documents. It defines the structure, types, and constraints of JSON data — useful for API validation, configuration files, and data contracts between services.
How does this tool work?
Paste a representative sample JSON object, and the tool inspects the types, values, and structure to infer a Draft 7 JSON Schema. It handles nested objects, arrays, strings with format hints, and numeric ranges.
Why use JSON Schema Generator online?
JSON Schema Generator in the browser saves context switching: no CLI install, no manual schema writing, and instant feedback. It is ideal for API development, debugging, and generating validation schemas for TypeScript, Zod, or Joi.
Tips for best results
Paste representative sample data covering all possible field types and values. Use strict mode for production validation. Review the generated schema carefully before using it in critical systems.
How to use
- Paste a sample JSON object into the input panel.
- Optionally enable descriptions, strict mode, or examples.
- Click Generate Schema.
- Review the generated schema in the output panel.
- Copy the schema or download it as a .json file.
- Need another utility? Scroll to Related Tools below for JSON Schema Generator companions on skybin.io.
Online tool vs terminal
| Terminal / CLI | This tool |
|---|---|
| Write schema definitions manually | Paste sample JSON and get a schema instantly |
| Cross-reference JSON types with spec docs | Auto-detect types, formats, and constraints |
| Debug nested structures by hand | Download the schema as a ready-to-use .json file |
Your JSON stays entirely in your browser. No data is sent to any server.
Frequently Asked Questions
- What is JSON Schema?
- JSON Schema is a specification for defining the structure, types, and constraints of JSON data. It allows you to validate JSON documents against a defined schema, ensuring data consistency in APIs and configuration files.
- Which draft version is supported?
- This tool generates JSON Schema Draft 7, the most widely supported version. It includes $schema declaration and supports all standard types, formats, and validation keywords.
- Can I use the generated schema for validation?
- Yes. The generated schemas are valid Draft 7 schemas and can be used with any JSON Schema validator (Ajv, Joi, Zod, TypeScript, etc.). Review the schema carefully for your use case.
- Does this tool handle nested objects and arrays?
- Yes. The generator recursively processes nested objects and arrays, inferring item types, required fields, and constraints at every level.
- Is this tool free to use?
- Yes. All Skybin developer tools are free with no account, API key, or usage limits.
- Does my data get sent to a server?
- No. All processing runs in your browser. Your JSON sample is never sent to any server.
- Can I use this on mobile?
- Yes. The tool works in modern mobile browsers, though a desktop screen is easier for reviewing large schemas.
- Are there keyboard shortcuts?
- Press Ctrl+Enter (or Cmd+Enter on Mac) in the JSON input to generate a schema. Copy and Download buttons provide one-click output.
- Does Skybin store my data?
- No. We do not log inputs or outputs. Refreshing the page clears in-memory state.