FREE · DEVELOPER TOOLS
JSON to TOON Converter.
Convert JSON to TOON (Token-Oriented Object Notation) and back to cut the size of data you send to LLMs, with a size comparison and a round-trip check.
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How to use JSON to TOON Converter
Paste JSON (or TOON to decode), choose the delimiter and copy the result. The round-trip check confirms nothing was lost.
How it works
Objects use indentation, arrays carry their length [N], and arrays of uniform flat objects become tables with a {field} header. Strings are quoted only when needed. Tested on thousands of random documents.
Example
Three users with id, name, role and active become one header users[3]{id,name,role,active}: and three short rows — about 40 % smaller than compact JSON.
Questions about JSON to TOON Converter
Is JSON to TOON Converter free, and do I need an account?
Yes. This tool is free to use in your browser without an account. Processing takes place on your device.
What are the limits and what should I check?
Token counts are estimates (about 4 characters per token). Everything is calculated in your browser; nothing you type is uploaded. Review the result before using it in your work.
Is my input sent to a server?
Your input is processed in your browser and is not uploaded by this tool. Files and pasted text are cleared when the page is refreshed. Normal website requests are still required to load the page and its libraries. Read the privacy explanation.