JSON to Swift Struct

How It Works

Paste any JSON data and instantly get Swift struct definitions with Codable conformance. The tool infers types from values, handles nested objects, arrays, null values, and mixed types. Configure the root struct name, Codable conformance, let vs var bindings, optional handling, and CodingKeys generation.

Features

• Codable conformance: struct Root: Codable { ... } by default for easy JSON encoding/decoding
• let / var binding: choose immutable let or mutable var properties
• Optional handling: null JSON values map to Any? optionals
• CodingKeys enum: auto-generate CodingKeys for snake_case or kebab-case JSON keys
• Nested struct inference: objects within objects generate separate named structs
• Accurate type mapping: String, Int, Double, Bool, Any?, and Swift array syntax [T]
• Array handling: homogeneous arrays get typed elements ([String]), mixed arrays use [Any]
• 5 example payloads: simple, nested, array, API response, config file
• Private: runs entirely in the browser — no data transmitted

Use Cases

• Generating Swift model types for API response decoding
• Bootstrapping Codable structs from JSON fixtures
• Converting JSON config files to typed Swift structs
• Learning how JSON structures map to Swift types