JSON to TOON Converter

Token-efficient format for LLMs • Cut token usage by ~50% • Eliminate JSON redundancy

JSON Input

TOON Output

About TOON Format

TOON (Token-Oriented Object Notation) is a compact data serialization format designed to reduce token usage when working with LLMs. Unlike JSON, which repeats field names for every object, TOON lists field names once and then just the values - like a lightweight table format.

Why TOON?

JSON can be wasteful for LLMs because it repeats structure even when nothing changes. TOON cuts token usage significantly (often by ~50%) by eliminating redundant keys, quotes, and braces while maintaining the same data structure.

Example

JSON (verbose): 
[
  { "id": 1, "name": "Alice", "role": "admin" },
  { "id": 2, "name": "Bob", "role": "user" }
]
TOON (compact): 
data[2]{id,name,role}:
  1,Alice,admin
  2,Bob,user