Generate modern Python 3.10+ / Pydantic V2 BaseModel classes for FastAPI schemas.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Paste your sample JSON payload into the editor.
Provide the root BaseModel class name.
Copy or download the generated Python schema file.
Yes, the output adheres to modern Pydantic V2 syntax (model_config, Field, Python 3.10+ types).
Nested object arrays are automatically extracted into distinct sub-models (e.g. UserItem).
Zero-egress companion tools in the Developer Tools suite
Format, validate, repair, and minify JSON data instantly.
Decode, verify claims, inspect headers, and check token expiry.
Test regex patterns with flags, group captures, and live matches.
Compare text or source code side-by-side with visual diffs.