Free browser-based tool

JSON to TOON Converter

Convert JSON to TOON specification 4.1 and TOON back to JSON using the official codec, strict decoding, round-trip checks, and size comparisons.

TOON specification 4.1 Official codec package 4.1.1, pinned and self-hosted
Guide

Convert JSON-shaped data to TOON for LLM prompt workflows

Token-Oriented Object Notation is a compact line-oriented representation of the JSON data model. It is designed primarily for LLM prompts and is especially effective for uniform arrays of objects.

ArrayText pins the official codec package to version 4.1.1 and identifies support as TOON Working Draft 4.1. Conversion includes strict decoding and a JSON-model round-trip equality check.

Common questions

JSON to TOON Converter FAQ

Does TOON always use fewer tokens than JSON?

No. Savings depend on data shape, JSON formatting, model, and tokenizer. Compact JSON can be smaller for irregular or deeply nested data.

Is TOON an official finalized standard?

No. Specification 4.1 is a working draft and the text/toon media type is provisional.

Is conversion lossless?

The official codec preserves the JSON data model. ArrayText verifies the generated TOON by decoding it and comparing the round-trip value.

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