JSON → Zod Generator
TypeScript Runtime Type Inference

JSON to Zod Schema Generator (TypeScript Runtime Validation)

Infer and generate TypeScript Zod schemas, type definitions, and nested validation rules from raw JSON payloads.

100% Client-Side Privacy
Zero Server Transmission
Presets:
Indent:
Nulls:
Mode:
Source JSON Payload
import { z } from "zod";

// --- Inferred Nested Sub-Schemas ---
OrderCustomerSchema = z.object({
    id: z.number().int(),
    fullName: z.string(),
    email: z.string().email(),
    phone: z.string(),
    tier: z.string(),
    loyaltyPoints: z.number().int(),
  });
OrderShippingAddressCoordinatesSchema = z.object({
      latitude: z.number(),
      longitude: z.number(),
    });
OrderShippingAddressSchema = z.object({
    street: z.string(),
    suite: z.string(),
    city: z.string(),
    state: z.string(),
    postalCode: z.string(),
    country: z.string(),
    coordinates: OrderShippingAddressCoordinatesSchema,
  });
OrderItemsItemSchema = z.object({
    sku: z.string(),
    title: z.string(),
    quantity: z.number().int(),
    unitPrice: z.number(),
    discount: z.number().nullable(),
    tags: z.array(z.string()),
    inStock: z.boolean(),
  });
OrderPaymentSummarySchema = z.object({
    currency: z.string(),
    subtotal: z.number().int(),
    tax: z.number(),
    shippingFee: z.number().int(),
    grandTotal: z.number(),
    transactionRef: z.string(),
    status: z.string(),
  });

// --- Root Schema Definition ---
OrderSchema = z.object({
  orderId: z.string().uuid(),
  orderNumber: z.string(),
  createdAt: z.string().datetime(),
  isFulfilled: z.boolean(),
  customer: OrderCustomerSchema,
  shippingAddress: OrderShippingAddressSchema,
  items: z.array(OrderItemsItemSchema),
  paymentSummary: OrderPaymentSummarySchema,
});

// --- Inferred TypeScript Types ---
OrderCustomer = z.infer<typeof OrderCustomerSchema>;
OrderShippingAddressCoordinates = z.infer<typeof OrderShippingAddressCoordinatesSchema>;
OrderShippingAddress = z.infer<typeof OrderShippingAddressSchema>;
OrderItemsItem = z.infer<typeof OrderItemsItemSchema>;
OrderPaymentSummary = z.infer<typeof OrderPaymentSummarySchema>;
Order = z.infer<typeof OrderSchema>;
Structural Complexity
Depth: 45 Sub-Schemas
Inferred Formats
3 Rules DetectedEmail, UUID, ISO, URL
TypeScript Exports
z.infer ONstrip

100% Client-Side AST Inference

Deep JSON parsing and Zod schema synthesis run entirely in your local browser sandbox with zero network telemetry.

Full TypeScript & Zod v3 Typing

Generates recursive z.object(), z.array(), smart union detection, and export type z.infer<typeof Schema> ready for production.

Smart Format & Coercion Rules

Automatically detects emails, UUIDs, ISO datetime strings, URLs, and numeric constraints with configurable strictness.

Technical Reference & Architecture Guide

JSON to Zod Schema Generator (TypeScript Runtime Validation) Developer Guide — Reference Guide

Infer and generate TypeScript Zod schemas, type definitions, and nested validation rules from raw JSON payloads.

Key Parameters & Controls

Root Schema NameString

Identifier name assigned to the top-level Zod schema and its exported inferred TypeScript type definition.

Default: RootSchema
Extract Sub-SchemasBoolean

Decomposes nested object hierarchies into standalone, reusable schema declarations named by their property keys.

Default: true
Smart Format DetectionBoolean

Automatically detects RFC 5322 emails, UUID v4, valid URLs, and ISO 8601 datetimes, applying .email(), .uuid(), .url(), and .datetime().

Default: true
Coercion ModeBoolean

Wraps primitive validations in z.coerce (e.g., z.coerce.number(), z.coerce.date()) to cast string inputs during runtime parsing.

Default: false
Null Handling StrategyEnum (nullable | nullish | optional)

Determines whether missing or null JSON values produce .nullable(), .nullish() (nullable and optional), or .optional().

Default: nullable
Object StrictnessEnum (strip | strict | passthrough)

Governs handling of unknown keys: .strip() (silently drops keys), .strict() (throws validation error), or .passthrough() (preserves keys).

Default: strip

Pro Tips & Best Practices

Array Element Union Unification

When converting heterogeneous JSON arrays, the tool synthesizes a normalized union schema (z.union([...])) or marks conflicting properties as optional union fields.

Safe Parsing in Production APIs

Prefer schema.safeParse(data) over schema.parse(data) in production endpoints to handle validation failures gracefully without try/catch overhead, returning a typed { success, data/error } result.

Zero-Overhead Static Type Extraction

Leverage export type Root = z.infer<typeof RootSchema>; to maintain bidirectional synchronization between TypeScript compile-time contracts and runtime validations without duplicate interfaces.

Data Sanitization via Transform Chaining

Chain Zod transforms like .trim(), .toLowerCase(), or .transform(val => new Date(val)) directly onto generated schemas to sanitize and transform data concurrently during parsing.

Common Gotchas & Troubleshooting

ZodError: Unrecognized keys detected when parsing incoming API responses

The schema strictness is set to .strict(). Switch to the default .strip() if third-party APIs return extraneous undocumented fields, or select .passthrough() to retain unknown properties.

ISO date strings fail validation or fail to instantiate as Date objects

ISO 8601 date strings are validated as z.string().datetime(). If native JavaScript Date instances are required, enable Coercion Mode (z.coerce.date()) or append .transform((val) => new Date(val)).

Empty JSON arrays infer as z.array(z.unknown()) or z.array(z.any())

Empty arrays contain no sample elements from which to deduce schema types. Provide at least one representative sample object inside the array in your source JSON.

Frequently Asked Questions

What is the difference between TypeScript interfaces and Zod schemas?▼

TypeScript interfaces are compile-time contracts erased during compilation, providing zero runtime protection against external data. Zod schemas execute at runtime to validate, parse, and sanitize API payloads while deriving identical static TypeScript types via z.infer.

How does the generator handle heterogeneous data types in JSON arrays?▼

The generator inspects all array items. When conflicting types or distinct object shapes are detected across items, it synthesizes a z.union([...]) construct or optional properties to accommodate all observed variants safely.

Is my JSON payload or schema uploaded to any server or cloud API?▼

No. All AST traversal, format pattern evaluation, and Zod code generation run 100% locally in your browser memory via Web Workers. No data is logged, stored, or transmitted over the network.

Can I convert the generated Zod schemas into JSON Schema or OpenAPI specifications?▼

Yes. The generator includes a dedicated JSON Schema tab. Furthermore, packages such as zod-to-json-schema or @asteasolutions/zod-to-openapi can bridge generated Zod schemas into OpenAPI/Swagger contracts in your codebase.

Does the generator support modern Zod v3 features like z.coerce and .datetime()?▼

Yes. It fully supports modern Zod v3 syntax, including z.string().datetime(), z.coerce, .nullish(), .strict(), and idiomatic z.infer static type extractions.

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