What Swift types are generated?

Strings become String, integers become Int, floats become Double, booleans become Bool, and null values become Any?. Nested objects become separate struct types with PascalCase names. Arrays become [T].

How does the tool handle Codable conformance?

Every struct conforms to Codable. When a JSON key differs from the Swift property name, a CodingKeys enum is generated with case mappings. This preserves the original JSON key mapping while following Swift naming conventions.

How are optional fields handled?

Fields that are missing from some items in an array are made optional with the ? suffix (e.g., Int? for optional integers). This is compatible with Swift's optional chaining.

DevBento

Tools/JSON to TypeScript & 8+ Languages Generator/Generate Swift Structs from API Response

Generate Swift Structs from API Response

Generate Swift Codable structs from a typical REST API JSON response. Paste your API JSON output and get typed Swift Codable structs for Xcode projects.

Output

Root name

Import path

JSON Input

TypeScript Output

// Generated by DevBento — json-to-typescript
interface RootAddress {
  street: string;
  city: string;
  zip: string;
}

interface RootPostsItem {
  title: string;
  likes?: number;
}

interface Root {
  id: number;
  name: string;
  email: string;
  isActive: boolean;
  roles: string[];
  address: RootAddress;
  posts: RootPostsItem[];
}

Send to:

Paste JSON to pretty-print, minify, validate, or visualize as an interactive graph. Syntax highlighting, tree view, and graph view with export.

ymlJSON / YAML / TOML / CSV / XML / HTML / Markdown

Convert between JSON, YAML, TOML, CSV, XML, HTML, Markdown, and .env in your browser. Paste config or API data and get the equivalent format instantly.

Generate Swift Structs from API Response

This example generates Swift Codable structs from a typical REST API response. The pre-filled JSON represents a user object with nested address, array of roles, and array of post objects. Switch to Swift mode to see the generated structs.

What You Get

The tool produces:

A root Root struct conforming to Codable
RootAddress struct for the nested address object
RootPostsItem struct for array items
CodingKeys enum when property names differ from JSON keys
camelCase property names following Swift conventions
Optional types (T?) for optional fields
Swift type mappings: String, Int, Double, Bool, [String]

How to Use

The example loads with a sample API response and Swift mode pre-selected
Inspect the generated Swift structs and their Codable conformance
Copy the structs and paste them into your Swift project
Replace with your actual API response to generate structs for your endpoints

Real-World Pattern

Swift Codable structs are the standard way to decode JSON in iOS and macOS apps. The generated code works directly with JSONDecoder().decode(T.self, from: data). Use optional types for fields that may not always be present in the response.

🔒

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