Free JSON to TOON Converter - Reduce API Costs with TOON Format

Convert JSON to TOON serialization format and reduce LLM tokens by 30-60%. Lower GPT-4 token costs and Claude API costs with our free converter.

JSON Input0 tokens
TOON Output0 tokens

Official Language Implementations

TOON is available in 4 stable languages. Choose your preferred language and see how to integrate TOON into your projects.

Installation

View Repository
npm install @toon-format/toon

Usage Example

import { encode, decode } from '@toon-format/toon';

// Your JSON data
const data = {"name": "Alice", "age": 30};

// Convert to TOON format
const toonString = encode(data);
console.log(toonString);
// Output:
// name: Alice
// age: 30

// Convert back to JSON
const jsonData = decode(toonString);

Key Features

  • 30-60% token reduction
  • Full spec compliance
  • Browser & Node.js support
  • TypeScript types included
Format Comparison

JSON vs TOON: Which Format is Better for LLMs?

See the difference between JSON and TOON serialization format. TOON format reduces LLM tokens while maintaining perfect data clarity.

Traditional JSON Format

156 tokens · Standard format

{
  "users": [
    {
      "id": 1,
      "name": "Alice Johnson",
      "email": "alice@example.com",
      "role": "admin"
    },
    {
      "id": 2,
      "name": "Bob Smith",
      "email": "bob@example.com",
      "role": "user"
    },
    {
      "id": 3,
      "name": "Carol Davis",
      "email": "carol@example.com",
      "role": "user"
    }
  ]
}

TOON Serialization Format

68 tokens · 56% reduction 🎉

users[3]:
  id: 1, 2, 3
  name: Alice Johnson, Bob Smith, Carol Davis
  email: alice@example.com, bob@example.com, carol@example.com
  role: admin, user, user

TOON vs JSON: Detailed Comparison

FeatureJSON FormatTOON Format
Token Efficiency
High redundancy
30-60% reduction
Human Readability
Good
Excellent
API Cost Savings
Standard costs
Significant savings
LLM Compatibility
Universal
GPT-4, Claude, Gemini
Repeated Keys
Every object
Only once
Array Syntax
Verbose brackets
Compact tabular

Winner: TOON Format for LLM Applications

While JSON remains the standard for web APIs, TOON serialization format is specifically optimized for Large Language Models. Use TOON to reduce GPT-4 token costs, Claude API costs, and improve overall LLM efficiency.

✓ 30-60% fewer tokens✓ Lower API costs✓ Better readability✓ Perfect for GPT-4 & Claude

How to Use JSON to TOON Converter?

1

Paste Your JSON Data

Simply copy your JSON and paste it into the input area. Our converter supports all standard JSON formats. Not sure what to try? Click "Load Example" to see a ready-made JSON-to-TOON conversion in action.

2

Customize TOON Output

Tailor the TOON format to your needs. Select your preferred delimiter (comma, tab, or pipe), adjust indentation size, and toggle length markers to optimize readability and efficiency.

3

Instantly Convert to TOON

As you type or paste your JSON, watch it transform into TOON format in real time. The converter provides a clean, human-readable TOON output optimized for LLM prompts and data serialization.

4

Copy or Download Your TOON Data

Once converted, click "Copy" to save it to your clipboard or hit "Download" to export the TOON file. Conversion is fast, accurate, and completely local, no data ever leaves your browser.

Why Convert JSON to TOON Serialization Format?

Reduce API costs and optimize GPT-4 token usage with TOON format. Save money on LLM API costs, reduce LLM tokens by 30-60%, and streamline your AI workflows with the most efficient serialization format for ChatGPT, Claude, and Gemini.

Reduce LLM Tokens by 30-60%

TOON serialization format eliminates redundant JSON syntax like brackets, braces, and repeated keys — reducing LLM tokens by up to 60% based on official benchmarks. Perfect for GPT-4 token optimization.

Reduce API Costs Significantly

Lower GPT-4 token costs and Claude API costs with TOON format. Reduce API costs by 30-60% on average across GPT-4, Claude, Gemini, and other LLMs. See immediate cost savings on every API call.

Completely Free Forever

No account required, no credit card, no limits. Convert unlimited JSON to TOON anytime, anywhere — 100% free forever.

Your Data Never Leaves Your Device

All conversion happens locally in your browser. Zero data transmission, zero servers, zero tracking. Your JSON stays private, guaranteed.

Instant TOON Format Conversion

Convert JSON to TOON serialization format in under 100ms. Real-time processing with immediate token reduction results — perfect for optimizing GPT-4 API calls and reducing LLM tokens instantly.

JSON ↔ TOON Bidirectional Conversion

Convert JSON to TOON format for LLM prompts to reduce API costs, then convert TOON back to JSON when needed. Lossless conversion preserves your data structure perfectly.

Got Questions? We've Got Answers

Frequently Asked Questions

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with TOON Format?

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