JSON to TOON Converter
Convert JSON to TOON and cut LLM tokens by 30â60%.
Convert JSON to TOON
TOON (Token-Oriented Object Notation) is a compact, line-oriented encoding of the JSON data model designed to feed structured data to large language models using far fewer tokens. Uniform arrays of objects are written as a single header plus tabular rows, eliminating repeated keys and punctuation.
How it saves tokens
- Object keys in an array are declared once as a header
- Rows drop braces, quotes, and repeated field names
- Indentation replaces brackets for nested structures
- Typical savings of 30â60% versus pretty-printed JSON
Lossless structure
TOON encodes the same data model as JSON â objects, arrays, strings, numbers, booleans, and null. Strings that contain delimiters or look like other types are quoted so the structure round-trips back to JSON.
Why it matters for LLMs
Every token sent to an LLM costs money and consumes the context window. When you pass tabular data â rows of users, products, or events â JSON wastes tokens repeating the same keys on every record. TOON declares the keys once, dramatically shrinking large datasets while staying readable to the model.
100% Private & Processed Locally
Every conversion on this page runs entirely inside your browser using JavaScript. Your data is never uploaded to a server, logged, or stored â making this tool safe even for sensitive payloads such as API responses, configuration files, and access tokens.
Because there is no network round-trip, conversions are instant and work even when you are offline. It is free to use with no sign-up, no rate limits, and no ads injected into your output.
Frequently Asked Questions
Common questions about the JSON to TOON Converter.