JSON to Swift Codable Generator

Paste a JSON object or API response and get ready-to-use Swift Codable structs with inferred types, nested models and optional fields. Runs in your browser.

Free No sign-up Runs in your browser
Input JSON
Output Swift

How to use the JSON to Swift

  1. Paste your JSON into the input box, or open a file.
  2. Adjust the options if needed. The output updates as you type.
  3. Copy the Swift or download it as a file.

About JSON

JSON (JavaScript Object Notation) is the default data format of web APIs, package manifests and most configuration tooling. It supports objects, arrays, strings, numbers, booleans and null.

How it works

Nested objects become their own Codable structs, arrays of objects are merged so every key is covered, and fields that are missing or null in some items are marked optional.

Private by design

Developer data is often sensitive: API responses, tokens, customer records, internal configs. This JSON to Swift processes everything locally in your browser tab. There is no server round-trip, no logging and no storage of your input.

Frequently asked questions

Is this JSON to Swift free?

Yes. This JSON to Swift is completely free to use with no sign-up, no limits and no ads inside the tool.

Is my data uploaded to a server?

No. The JSON to Swift runs entirely in your browser using JavaScript. Nothing you paste is sent to DevT Pro or any other server.

How are Swift types inferred?

Nested objects become their own Codable structs, arrays of objects are merged so every key is covered, and fields that are missing or null in some items are marked optional.

Can I use the JSON to Swift offline?

Yes. JSON to Swift is also built into DevT Pro, a native app for Mac, Windows, iPad and Linux with 120+ developer tools that work fully offline. It is a $5.99 one-time purchase with no subscription.

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DevT Pro

JSON to Swift, offline, plus 120+ developer tools.

Converters, formatters, encoders, validators, code generators and more in one native app. No internet, no account, no uploads.

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