Does it generate CodingKeys?

Yes, whenever a JSON key differs from the camelCase Swift property name a CodingKeys enum is added automatically.

Null values become optionals. Adjust the generated type manually if the real API can return a non-string value.

Can I generate classes instead of structs?

Yes, turn off the struct toggle to emit final classes conforming to Codable.

Is my data uploaded to a server?

No. This tool runs entirely in your browser using standard web APIs, so your input never leaves your device and nothing is logged or stored on our servers.

Does it work offline and on mobile?

Yes. Once the page has loaded it keeps working without a network connection, and the layout is responsive so it stays usable on phones and tablets.

JSON to Swift Codable Converter

Turn JSON into Swift structs that conform to Codable.

Support

Works Offline

Privacy First

No Login

No API

Root type name

struct (off = class)

Nulls as optionals

CodingKeys for snake_case

JSON input

Swift Codable models

import Foundation

struct Root: Codable {
    let id: Int
    let fullName: String
    let isActive: Bool
    let score: Double
    let tags: [String]
    let address: Address
    let nickname: String?

    enum CodingKeys: String, CodingKey {
        case id
        case fullName = "full_name"
        case isActive = "is_active"
        case score
        case tags
        case address
        case nickname
    }
}

struct Address: Codable {
    let city: String
    let zipCode: String

    enum CodingKeys: String, CodingKey {
        case city
        case zipCode = "zip_code"
    }
}

About the JSON to Swift Codable Converter

Paste an API response and get idiomatic Swift models: nested structs or classes conforming to Codable, camelCase properties with CodingKeys for snake_case JSON keys, optionals for null values and typed arrays. Everything is generated locally in your browser, so private payloads never leave your machine.

Examples

Snake case key

{"full_name":"Ada"}

Output

let fullName: String + CodingKeys

Keyboard shortcuts

Copy the main outputCtrl / ⌘ + Shift + C
Download the resultCtrl / ⌘ + S
Share this toolCtrl / ⌘ + Shift + S
Reset the inputsAlt + R
Open the tool search paletteCtrl / ⌘ + K

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Frequently asked questions

Version 1.0.0 · Updated 2026-08-23 · Runs entirely in your browser

JSON to Swift Codable Converter

About the JSON to Swift Codable Converter

Examples

Keyboard shortcuts

Related tools

iOS .strings ↔ JSON Converter

Plist ↔ JSON Converter (Info.plist)

Android strings.xml ↔ JSON Converter

Csv To Json

Csv To Markdown Table

CSV to SQL INSERT

Frequently asked questions

Does it generate CodingKeys?

How are nulls typed?

Can I generate classes instead of structs?

Is my data uploaded to a server?

Does it work offline and on mobile?