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JSON Schema Generator

Infer a JSON Schema from sample data—then tighten rules for your API contract.

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Schemas from real payloads

Writing schemas from scratch is tedious. CalcForge inspects example JSON and drafts a JSON Schema capturing object shapes, array items, and primitive types—giving you a baseline to add enums, formats, and constraints before publishing contracts.

Good fits

  • Bootstrapping OpenAPI component schemas from production samples
  • Creating validation rules for config files checked in CI
  • Documenting expected webhook shapes for partners
  • Pairing with codegen tools for typed clients plus runtime checks
Sample:
{"email":"ada@example.com","age":30}

Generated excerpt:
{"type":"object","properties":{"email":{"type":"string"},"age":{"type":"integer"}}}

Practical notes

  • One sample under-specifies optionals—merge schemas from multiple examples.
  • Add `format`, `pattern`, and `enum` manually for production-grade contracts.
  • Validate instances with JSON Schema Validator after editing generated output.

Frequently asked questions

Are all fields marked required?

Keys present in the sample often become required. Remove or relax requirements when fields are optional in real traffic.

Can it infer string formats like email or date?

Heuristics may suggest formats—always confirm against your domain rules before publishing.

Does it support array tuple schemas?

Homogeneous arrays are inferred easily. Mixed tuple arrays may need manual `prefixItems` editing.

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