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Published: June 2026By Web Util Slyce Team

JSON to Swift Guide

Convert JSON to Swift Codable structs instantly. Generate type-safe Swift structs with Codable conformance from JSON samples. Use our free online tool to get started instantly.

What is JSON to Swift?

JSON to Swift is a free online tool that convert json to swift codable structs instantly. generate type-safe swift structs with codable conformance from json samples. It processes everything locally in your browser, so your data never leaves your device. Whether you are a developer looking to streamline your workflow or a professional needing quick and reliable results, this tool delivers instant, privacy-focused functionality without requiring any sign-up or software installation.

How to Use JSON to Swift

Using JSON to Swift is straightforward. Follow these steps to get started:

Step 1: Paste your JSON
Copy your JSON data and paste it into the input textarea above.

Step 2: Configure options
Toggle nullable detection for optional property generation.

Step 3: Copy the Swift code
Click Generate, then copy the Swift structs or download the .swift file.

Key Features of JSON to Swift

JSON to Swift comes with a range of features designed to make json tasks easier:

Codable Generation: Creates Swift structs with Codable conformance, making them ready for JSON encoding/decoding.
Type Inference: Automatically detects String, Int, Double, Bool, arrays, and optional (?) types from your JSON.
Nested Structs: Creates separate struct definitions for nested objects with proper type references.
Local Processing: All conversion happens locally — your JSON never leaves your device.

Tips & Best Practices

Get the most out of JSON to Swift with these tips:

Include all JSON keys in sample data: Fields absent from your sample JSON will be absent from the generated struct. Ensure your sample includes every key that exists in your actual data.

Use CodingKeys for custom mappings: If your JSON keys don't match Swift naming conventions, add a CodingKeys enum to customize the mapping between Swift property names and JSON keys.

Frequently Asked Questions

What Swift version is targeted?

The generator targets Swift 5.0+ with Codable protocol support. The generated code uses standard Foundation Codable conformance with let properties.

How are null values handled?

Fields with null values are marked as optional with ? (e.g., String?). Fields with consistent non-null values are marked as non-optional.

Is my JSON data sent to a server?

No. All conversion happens locally in your browser.