JSON to F# Converter

Type Name:

JSON Input

F# Output

What is JSON to F# Converter?

Need to generate F# types and records from your JSON (JavaScript Object Notation) data? This tool does that instantly. Perfect for F# developers working with .NET applications, web services, or functional programming who need to deserialize JSON into strongly-typed F# types. Generate records, types, and type definitions automatically.

According to F# documentation, records and discriminated unions are perfect for JSON serialization. Our converter analyzes your JSON structure and generates proper F# types. First, validate your JSON using our JSON Validator, then convert it to F#. You can also format your JSON with our JSON Formatter first if needed.

Everything happens in your browser – your JSON never leaves your computer. Convert, download, and use your F# types right away.

How to Use JSON to F#

Follow these steps to convert JSON to F# types. Each step uses the actual buttons and panels on this page.

Paste, Upload, or Load Sample

Paste your JSON into the left JSON Input panel, or click Upload to load a .json or .txt file. Click Sample to see example JSON. Example input:

{"subscriberId":"SUB-1001","plan":"Unlimited 5G","dataUsage":45.2,"status":"active"}

Invalid JSON will show an error. Use our JSON Validator first if unsure. Configure type name in the options above.

View Generated F# Output

The right F# Output panel shows the generated F# types instantly. JSON objects become records, arrays become lists or arrays.

Download or Copy

Click Download to save the F# file, or Copy to copy to your clipboard. Use Clear on the input panel to start over. All processing runs in your browser.

When You'd Actually Use This

.NET Applications

Generate F# types from JSON API responses for .NET applications. Create models for REST APIs or JSON-based configurations. Perfect for F# web services or desktop applications.

Functional Programming

Create F# records from JSON data for functional programming projects. Generate immutable data models for JSON-based APIs or configurations. Perfect for F#'s functional paradigm.

Web Services

Generate F# types from JSON data for web services. Create data models for JSON-based APIs or configurations. Perfect for F# web frameworks.

Code Generation

Generate F# code from JSON data structures. Perfect for creating data models, DTOs, or entity types from JSON schemas or API responses.

Common Questions

Is my JSON data stored?

Nope. Everything happens right in your browser. Your JSON never leaves your computer – we don't even see it. Check out the ECMA-404 standard for more details.

How are JSON objects handled?

JSON objects become F# records. Properties become record fields, and nested objects become nested records or references. Arrays become F# lists or arrays. Check out the RFC 8259 for more details.

Can I use the generated F# code?

Yes. The generated F# code is valid and ready to use. Drop it into your F# project and start using it. You may want to review and refine the types for your specific use case.

What about JSON serialization?

The generated F# records work with System.Text.Json or Newtonsoft.Json for JSON serialization. You may need to add serialization attributes for custom property names.

Does it work with large JSON files?

Yep. Since everything happens in your browser, it depends on your device. Small to medium JSON structures convert instantly. Really huge structures might take a few seconds.

What F# version is supported?

The generated code works with F# 4.0 and later. It uses standard F# features and follows F# conventions for maximum compatibility.

Other JSON Tools You Might Need

Conversion is just one JSON task. Here are other tools that work well together: