JSON TOON Converter

Convert JSON to a compact, TOON-style notation and back — whitespace and key quotes removed, common key names shortened.

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Convert JSON to a compact, TOON-style notation

TOON (Token-Oriented Object Notation) is a compact format designed for passing structured data to large language models. This free converter produces a simplified, TOON-inspired notation — it is not the official TOON format. It keeps JSON's structure of braces, brackets and commas, but removes whitespace, drops the quotes around keys and shortens some common key names (for example name → n and id → i). It also converts that notation back to standard JSON, and a badge shows how many characters smaller the output is than the JSON you pasted.

How to convert JSON to the TOON-style notation

  1. On the JSON → TOON tab, paste your JSON or click Load Example.
  2. Click Validate JSON to catch syntax errors first, then Convert to TOON.
  3. Check the size badge and character counts, then Copy TOON to use the output.
  4. Switch to the TOON → JSON tab to convert the notation back, then Format or Minify the result.

When it is useful

  • Getting a shorter, single-line version of structured data — records, lists and config — to paste into a prompt or a note.
  • Seeing how much of a JSON document is whitespace and repeated key quotes.
  • Converting the notation back to standard JSON your code can parse.

Limits to know about

  • The badge counts characters, not tokens. Check real token counts with your model's tokenizer before relying on any saving.
  • Abbreviated keys are less self-explanatory, so tell the model what the short keys mean.
  • A key that already matches a short code (such as n) comes back expanded (as name), and keys containing anything other than plain letters, digits, _ or $ (a space or hyphen, for example) cannot be converted back.

Runs entirely in your browser

Conversion and validation happen locally in your browser — your JSON is never uploaded or stored, so prompt data and proprietary schemas stay on your device. Prefer to clean up standard JSON first? Pair this with our JSON formatter and validator.

Need a custom tool or internal developer utility built for your team? Get in touch with SR Infobiz.

Frequently Asked Questions

What is TOON format?

TOON (Token-Oriented Object Notation) is a compact format for passing structured data to large language models. This tool currently outputs a simplified, TOON-inspired notation rather than the official TOON format: it keeps JSON's braces, brackets and commas, but removes whitespace, drops the quotes around keys and shortens some common key names (for example name → n, id → i).

How much smaller is the output?

It depends on your data. Most of the reduction comes from removing whitespace and key quotes, so pretty-printed JSON shrinks a lot and already-minified JSON only a little; objects that use common key names such as id, name or status shrink further. The badge above the output compares character counts with the JSON you pasted. Characters are not tokens, so check token counts with your model's tokenizer before relying on any saving.

When should I use it instead of JSON?

Use it when you want a shorter, still-readable version of structured data to paste into a prompt or a note. Because some keys are abbreviated, tell the model what the short keys mean. Stay with standard JSON for APIs, config files and storage, where tools expect real JSON.

Is my JSON uploaded to your servers?

No. Conversion and validation run entirely in your browser, so your JSON and TOON never leave your device and nothing is logged or stored. That makes it safe to use with proprietary schemas and real prompt data.

Does it convert back to JSON without losing data?

Usually. The TOON to JSON tab expands the short key names and rebuilds equivalent JSON. Two limits: a key that already matches one of the short codes (such as n or i) is expanded on the way back (n becomes name), and keys containing anything other than plain letters, digits, _ or $ (a space or hyphen, for example) cannot be read back. Indentation and blank lines are not kept — use Format or Minify to lay the result out.

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