How does the generator handle optional fields (prop?: string)?

In TypeScript, optional properties denote fields that may be omitted. In JSON Schema, properties are optional by default unless listed in the 'required' string array. If strictNullChecks is active, 'prop?: string' excludes prop from 'required', while 'prop: string | null' keeps prop in 'required' but gives it type ['string', 'null'].

Which JSDoc tags are converted into JSON Schema validation rules?

The generator parses description comments into the 'description' keyword. Additionally, validation tags such as @minimum, @maximum, @minLength, @maxLength, @pattern, @format (e.g., uri, date-time, email, uuid), @default, and @deprecated are parsed directly into standard validation constraints.

What is the difference between Draft-07 and Draft 2020-12 output?

Draft-07 uses 'definitions' for reusable schemas and supports 'items' as an array for tuple validation. Draft 2020-12 uses '$defs', introduces 'prefixItems' for tuples, and allows $dynamicRef and independent keyword evaluation, making it ideal for modern API specifications and OpenAPI 3.1.

Can I convert multiple interfaces in a single TypeScript file?

Yes. When multiple interfaces or type aliases are present, you can designate a root interface name. All referenced types and nested interfaces will be generated as modular schema definitions under '$defs' or 'definitions', linked via relative $ref URIs.

TypeScript Schema Compiler

TypeScript Interface to JSON Schema Generator (Draft-07 & 2020-12)

Transform TypeScript interfaces, types, and JSDoc comments into standard JSON Schema definitions for API contracts and form builders.

Draft-07 & 2020-12 Conformance

Zero Server Transmission

Presets:

Draft Version:

Root Type:

Definitions Key:

Additional Properties:

Infer Smart FormatsParse JSDoc Annotations

Indentation:

TypeScript Interfaces & Types0 Types

/**
 * Core User Profile entity for enterprise authentication and RBAC
 * @title UserProfile
 * @description Primary identity record representing an authenticated user account
 */
UserProfile {
  /**
   * Primary system UUID v4 identifier
   * @format uuid
   */
  id: string;

/**
   * Validated primary email address
   * @format email
   */
  email: string;

/**
   * Unique handle or display username
   * @minLength 3
   * @maxLength 30
   * @pattern ^[a-zA-Z0-9_-]+$
   */
  username: string;

/**
   * Age in completed calendar years
   * @minimum 18
   * @maximum 120
   */
  age?: number;

/**
   * Account activation status
   * @default true
   */
  isActive: boolean;

/**
   * Access control security role
   */
  role: 'admin' | 'editor' | 'subscriber' | 'guest';

/**
   * Primary mailing and billing address
   */
  address: Address;

/**
   * Granted OAuth 2.0 permission scopes
   */
  permissions: string[];

/**
   * Account creation ISO-8601 timestamp
   * @format date-time
   */
  createdAt: string;

/**
   * Arbitrary key-value metadata tags
   */
  metadata?: Record<string, string>;
}

/**
 * Standardized postal and geolocation address definition
 * @title Address
 */
Address {
  street: string;
  suite?: string;
  city: string;
  state: string;
  /**
   * Postal or ZIP code
   * @pattern ^[0-9]{5}(?:-[0-9]{4})?$
   */
  postalCode: string;
  country: string;
  isPrimary?: boolean;
}

84 Lines•1435 Chars•1.4 KB (Bytes)

TypeScript AST Ready

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "EmptySchema",
  "type": "object",
  "properties": {}
}

2020-12 ($defs)•0 Definitions•0 Properties

0.1 KB Valid

Interfaces & Types

0AST parsed

JSON Schema Version

Draft 2020-12$defs

Properties & Rules

0rules synthesized

100% Client-Side AST Parsing

TypeScript interface extraction and schema compilation execute purely in your local browser sandbox. Zero data transmission or server logging.

Draft-07 & 2020-12 Conformance

Full compatibility with standard JSON Schema specifications including $defs/definitions, tuple prefixItems, strict typing, and enum generation.

JSDoc & Smart Constraint Inference

Extracts @description, @minimum, @maximum, @format, @pattern, @default directly from code comments to synthesize rich OpenAPI-grade schemas.

TypeScript Interface to JSON Schema Generator (Draft-07 & 2020-12)

100% Client-Side AST Parsing

Draft-07 & 2020-12 Conformance

JSDoc & Smart Constraint Inference

TypeScript Interface to JSON Schema Generator (Draft-07 & 2020-12) — Reference Guide

Key Parameters & Controls

Pro Tips & Best Practices

Use standard JSDoc tags like

Draft-07 vs Draft 2020-12 Definitions

Unions vs Discriminated Unions

Common Gotchas & Troubleshooting

Circular and Recursive Type References

Complex Mapped and Utility Types (Omit, Pick, Partial)

Frequently Asked Questions

Related Tools & Utilities