Convert JSON to TOON format

TOON (Token Oriented Object Notation) is designed to minimize redundant text tokens found in JSON. By compressing repetitive keys and representing structured data in a more compact, deterministic form, TOON reduces the total token count processed by large language models (LLMs), which directly lowers API usage costs and improves performance during prompt serialization.

About TOON Format

TOON (Token Oriented Object Notation) is a modern, compact data format designed to represent structured data with minimal repetition. It’s optimized for token-efficient processing in LLM (Large Language Model) workflows. Arrays of objects are represented as schema-based tables for better compression and readability.

What This Tool Does

This converter takes any valid JSON input and converts it into its equivalent TOON (v0.7) format. Nested arrays and object lists are automatically converted into TOON’s schema representation — for example:

Input:
{
  "users": [
    {"id": 1, "name": "Alice"},
    {"id": 2, "name": "Bob"}
  ]
}

Output:
users[2]{id,name}:
  1,Alice
  2,Bob

How to Use

  1. Paste or type your JSON data into the left input box.
  2. The converted TOON will automatically appear on the right.
  3. Click Copy or Download to save the result.

Privacy

All conversions are processed entirely in your browser. No data is uploaded or stored on any server. You can safely use this tool offline or with sensitive data.

FAQs

Is TOON compatible with JSON?

Yes, TOON is derived from JSON and can be converted back easily using the same key-value mapping.

Why use TOON instead of JSON?

TOON is more compact and token-efficient, making it ideal for large language models (LLMs) and fast serialization.

Does this tool send my data anywhere?

No. All conversions happen entirely in your browser. Nothing is uploaded or stored remotely.