About JSON → Zod Schema

Derive a runtime-validatable Zod schema from a JSON sample. Part of the DevTools Surf developer suite. Browse more tools in the Converters collection.

Use Cases

• Generating Zod schemas from API response samples for type-safe validation
• Creating form validation schemas from existing JSON data structures
• Building runtime type guards for incoming webhook payloads
• Scaffolding tRPC input schemas from example request bodies

Tips

• Paste a JSON sample to generate a complete Zod schema
• Review inferred types — numbers vs strings may need adjustment
• Use the output directly in your TypeScript validation layer

Fun Facts

• Zod was created by Colin McDonnell in 2020 and quickly became the most popular TypeScript-first schema validation library, surpassing 20 million weekly npm downloads by 2024.
• Unlike JSON Schema, Zod schemas are executable TypeScript code that provides both compile-time types and runtime validation from a single source of truth.
• The name 'Zod' is a reference to General Zod from Superman — its logo features a stylized 'Z' inspired by the character.

FAQ

What's Zod?

A TypeScript-first schema validator. `z.object({...})` defines a runtime-validatable schema that also infers a TypeScript type. Widely used in Next.js/React apps and tRPC.

How is this different from json-to-typescript-types?

That tool generates a compile-time type. Zod gives you both the type (via `z.infer`) and a runtime validator that checks incoming JSON matches.

Does it detect optional fields?

Fields that appear inconsistently across records become `.optional()`. Always-present fields are required. Small sample sizes can mislead — review.

What about refinements (min, max, regex)?

Not auto-inferred — the sample doesn't tell us what constraints matter. Add `.min(1)`, `.max(100)`, `.regex(...)` manually after generation.