Tools · Developer Tools
JSON to Code Generator
Infer types from a JSON sample and generate C#, TypeScript, Java, Python, or Go. Conversion stays in this browser.
Inference runs in your browser from the sample you paste. Mixed arrays use a safe union or fallback type instead of guessing. API: None.
How to generate types
- Paste a representative JSON sample. Invalid JSON should be fixed in the JSON Formatter first.
- Choose a language and options, then generate.
- Copy or download the file and review names, nullability, and numeric types against a second sample.
FAQ
Is the JSON uploaded or sent to an AI model?
No. Types are inferred in this browser. There is no AI generation step.
What happens with mixed arrays?
Heterogeneous arrays become a union or a fallback type such as object or any. The generator does not invent a single concrete type.
How are JSON keys preserved?
C# can emit JsonPropertyName or Newtonsoft attributes, Go uses json tags, and TypeScript quotes keys that are not identifiers.
Can I still open the old JSON to C# URL?
Yes. /tools/json-to-csharp and language aliases share this page and engine.
Which languages are generated for real?
C#, TypeScript, Java, Python, and Go. Languages that are not implemented are not listed.
What if the JSON is invalid?
Generation stops with a line-aware error and a link to the JSON fixer. Nothing is invented from broken input.
Read the original guide: Turn sample JSON into C#, TypeScript, Java, Python, or Go.