JSON to Swift Converter
ConvertersGenerate Swift structs conforming to Codable from a JSON object instantly in your browser. Powered by quicktype-core. UML class diagram view. Client-side.
JSON →
Swift
JSONjson
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Swiftswift
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Input: 315 chars
About JSON to Swift Converter
The JSON to Swift converter uses `quicktype-core` with `just-types: true` and `initializers: false` to produce Swift `struct` types that conform to `Codable`. A post-processing step removes runtime helpers, leaving clean Swift type declarations. Output is prettified with js-beautify. The UML class diagram panel shows the inferred struct hierarchy.
Features
- ✓Powered by quicktype-core with just-types and no initializers
- ✓Generates Swift structs conforming to Codable (Encodable + Decodable)
- ✓Post-processed to keep only struct declarations
- ✓UML class diagram view shows the inferred struct hierarchy
- ✓Handles nested objects → nested Swift structs
- ✓Handles arrays → [T] array properties
- ✓Optional fields use T? annotations
- ✓CodingKeys enum generated for non-Swift-idiomatic JSON key names
- ✓Download generated Swift as a .swift file
- ✓Copy output to clipboard in one click
- ✓Web Worker processing — never blocks the UI
- ✓100% client-side — data never leaves your browser
Common Use Cases
- Generating Swift Codable structs from JSON API responses for iOS apps
- Creating Swift model types from JSON payloads for URLSession or Alamofire
- Scaffolding Swift data structures from JSON configuration files
- Reverse-engineering JSON to Swift types for SwiftUI or UIKit apps
Frequently Asked Questions
QAre the structs ready to use with JSONDecoder?
Yes — the generated structs conform to Codable and work directly with Swift's JSONDecoder and JSONEncoder.
QIs my data sent to a server?
No. quicktype-core runs in a Web Worker inside your browser.