TOON (Token-Oriented Object Notation) is a data serialization format designed specifically for LLM prompts to be highly efficient. It dramatically reduces token usage by 30-60% compared to JSON while remaining structured and human-readable. By using a tabular format for arrays and minimal syntax for objects, TOON makes your data cheaper and faster to process with AI models.

What's the difference between TOON and JSON?

The key difference is token efficiency. JSON is verbose, with brackets, quotes, and commas that consume tokens. TOON is a more compact syntax designed for LLMs, representing arrays as tables with headers and using minimal punctuation. This efficiency directly translates to significant cost savings on your LLM API bills, especially for large or repeated datasets.

How much can I save with TOON?

You can typically expect to save 30-60% on LLM tokens compared to using JSON. For large datasets or frequent API calls, this translates directly into significant cost savings. Data with repeated structures, like API responses or database results, often sees savings at the higher end of this range (40-60%).

Is TOON compatible with all LLMs?

Yes. TOON is a simple text format that works flawlessly with all major large language models, including those from OpenAI (GPT-4), Anthropic (Claude), Google (Gemini), and Meta (LLaMA). Since any LLM can process plain text, they can all be instructed to understand and parse the TOON format with a simple instruction in your prompt.

Can I convert TOON back to JSON?

Absolutely. TOON is fully and losslessly reversible. Our converter tool supports bidirectional conversion, meaning you can convert TOON back to the exact original JSON structure without any data loss. This allows you to use TOON for efficiency and then convert back to JSON for compatibility with other tools.

What types of data work best with TOON?

TOON can represent any valid JSON data, but it delivers the highest token savings (40-60%) on uniform tabular data. This includes database query results, API responses with lists of objects, analytics data, or product catalogs. While TOON fully supports nested objects and arrays, the token reduction is most dramatic with flatter, more repetitive data structures.

Is my data safe when using this converter?

100% safe. All conversion from JSON to TOON (and back) happens locally in your browser. Your data is never sent to any server, never stored, and never seen by us. The converter even works offline once the page has loaded, guaranteeing your information remains private.

Yes, completely free. Both this TOON converter and the underlying TOON format specification are open and free to use without any limits, file size restrictions, or premium features. It's an open-source effort to make working with LLMs more efficient for everyone.

Conditions d'utilisation

Dernière mise à jour : 12/27/2025

1. Acceptation des conditions

En accédant et en utilisant JSON to TOON Converter (le « Service »), vous acceptez d'être lié par les termes et dispositions de cet accord.

2. Description du service

Le service fournit un outil côté client pour convertir les données entre les formats JSON et TOON. Le Service est fourni « tel quel » et est destiné à votre usage personnel et non commercial.

3. Exclusion de garanties

Le Service est fourni sans garantie d'aucune sorte. Nous ne garantissons pas que le service répondra à vos exigences, sera exempt d'erreurs ou que les résultats de l'utilisation du service seront précis ou fiables. Vous êtes responsable de la validation de la sortie du convertisseur.

4. Limitation de responsabilité

En aucun cas JSON to TOON Converter, ses créateurs ou ses sociétés affiliées ne pourront être tenus responsables de tout dommage direct, indirect, accidentel, spécial ou consécutif découlant de l'utilisation ou de l'incapacité d'utiliser le service.

5. Modifications des conditions

Nous nous réservons le droit de modifier ces conditions de temps à autre, à notre seule discrétion. Par conséquent, vous devriez consulter cette page périodiquement. Votre utilisation continue du Service après une telle modification constitue votre acceptation des nouvelles Conditions.