JSON Key Extractor

Free online JSON key extractor — flatten nested JSON to dot-notation keys instantly. Useful for API docs, schema discovery, and TypeScript interfaces.

FAQ

What is dot-notation for JSON keys?

Dot-notation flattens nested JSON into single-level key paths. For example, {"user":{"name":"Alice"}} becomes user.name. Array items appear as key[0], key[1], etc.

Why extract JSON keys?

Extracting all dot-notation keys is useful for documenting API schemas, generating TypeScript types, or understanding a deeply nested JSON structure at a glance.

Does it include array indices?

Yes. Array elements are referenced as parentKey[0], parentKey[1], and so on.

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