TOON is a compact, human-and-LLM-readable serialization format designed for AI context windows that combines YAML-like indentation for nested objects with tabular header folding for arrays of objects.
Convert JSON to TOON (Token-Oriented Object Notation)
Compress verbose JSON payloads into LLM-friendly Token-Oriented Object Notation to cut prompt token usage by up to 60%.
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Key Capabilities
Engine Features & Specifications
Slash LLM API Context Costs by 40–60% with TOON
Standard JSON repeats every property key name on every single object in an array and burns thousands of tokens on quotes, colons, and curly braces. TOON declares schemas once and streams compact positional values.
How Tabular Header Folding Eliminates Repeated JSON Keys
An array of 100 user objects in JSON repeats `"id"`, `"name"`, `"email"`, and `"role"` 100 times. TOON folds uniform object arrays into a single header declaration (`users[100]{id,name,email,role}:`) followed by clean value rows.
Live Token Savings Benchmark (JSON vs. Minified JSON vs. TOON)
See the exact token count and percentage saved in real time before copying your TOON block into your system prompt or RAG pipeline.
Common Inquiries
Frequently Asked Questions
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