JSON Schema Validator
Check if your JSON matches a schema or create a new schema from your data. We support all JSON Schema drafts, can generate TypeScript types, and have ready-made templates for common formats like emails, dates, and URLs. Everything runs in your browser.
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JSON Data
JSON Schema
Everything You Need for Schema Validation
Validate data, generate schemas, and create TypeScript types—all in one place.
Schema Validation
See if your data fits the schema. Supports all major drafts (4, 6, 7, 2019-09, 2020-12). Get instant error messages showing exactly where things don't match.
Pre-built Patterns
Pick from ready-made schemas for emails, URLs, dates, phone numbers, and more. No need to write from scratch.
Auto-Generate Schema
Paste your data, hit Generate, and get a complete schema. Perfect for creating validation rules fast or documenting your API structure.
TypeScript Types
Convert schemas to TypeScript interfaces instantly. No manual typing—get type-safe code in seconds.
Clear Error Messages
See exactly what's wrong and where. Errors show the path, expected type, and what you actually have. Makes fixing problems quick.
All Draft Versions
Works with Draft 4, 6, 7, 2019-09, and 2020-12. Just pick whichever version your project uses.
How It Works
Three steps to validate your data.
Add Your Data
Paste it in or upload a file. That's it.
Add a Schema
Generate one from your data, pick a pre-built pattern, or paste your own.
See Results Instantly
Validation happens automatically. Errors appear in the sidebar with exact locations. When valid, generate TypeScript types if you need them.
Frequently Asked Questions
What is schema validation?
It checks if your data matches a set of rules: structure, types, required fields, formats. Catches problems before they cause issues.
Which schema versions work?
All of them. Draft 4, 6, 7, 2019-09, and 2020-12. Pick the one you need from the dropdown.
Can I auto-generate a schema?
Yep. Paste your data, click "Generate Schema," and it'll figure out types, required fields, and patterns. You can customize it after.
What's TypeScript generation for?
It turns your schema into TypeScript interfaces. Skip writing types by hand—just click 'TypeScript' and copy the code.
How do errors look?
They show the path, expected type, and what you actually have. Like "data.email should match format 'email'" or "data.age should be number." Makes fixing stuff quick.
Is my data safe?
Everything runs in your browser. Nothing gets sent to any server—your data never leaves your device.