ISON – Data format that uses 30-70% fewer tokens than JSON for LLMs
ISON (Interchange Simple Object Notation) - a data format optimized for LLMs and Agentic AI. The problem: JSON wastes tokens. Curly braces, quotes, colons, commas - all eat into your context window. ISON uses tabular patterns that LLMs already understand from training data: JSON (87 tokens): { "users": [ {"id": 1, "name": "Alice", "email": "[email protected]"}, {"id": 2, "name": "Bob", "email": "[email protected]"} ] } ISON (34 tokens): table.users id:int name:string email 1 Alice [email protected] 2 Bob [email protected] Features: - 30-70% token reduction - Type annotations - References between…
ISON – Data format that uses 30-70% fewer tokens than JSON for LLMs launched on December 26, 2025 with 7 votes, #1,248 of 11,628 launches that month and more than 75% of that year's launches.
What it does
🔥 Token-efficient JSON alternative for LLMs & agentic AI — same data, fewer tokens. Python · JS/TS · Rust · Go · C++ - ISON-format/ison
In the maker’s words, at launch
ISON (Interchange Simple Object Notation) - a data format optimized for LLMs and Agentic AI. The problem: JSON wastes tokens. Curly braces, quotes, colons, commas - all eat into your context window. ISON uses tabular patterns that LLMs already understand from training data: JSON (87 tokens): { "users": [ {"id": 1…
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