Independent measurement: TOON vs CSV vs JSON on Claude, Gemini and GPT tokenizers

[johnisking]

We measured the same flat 20-row table (7 fields) in 8 formats on four tokenizers. TOON saved 65–69% vs indented JSON, but CSV was 4–9% smaller than TOON on every tokenizer (e.g. GPT o200k: CSV 429, TOON 474). This matches the expectation that TOON's advantage is on nested or mixed data rather than flat tables. Data and inputs (CC BY 4.0): https://tokensave.app/data/token-cost-by-format