How to use the CSV to TOON
- Paste your CSV into the input box, or open a file.
- The output updates automatically as you type.
- Copy the TOON or download it as a file.
About CSV
CSV (comma-separated values) is the universal format for spreadsheets and data exports. The first row holds column names and each following row is one record.
About TOON
TOON (Token-Oriented Object Notation) is a compact encoding of JSON designed for LLM prompts. It uses YAML-style nesting and CSV-style rows for uniform arrays, typically cutting token counts substantially compared with JSON.
How it works
The first row is used as column names. Numbers and booleans are detected automatically, and dotted headers such as address.city are expanded back into nested objects.
Private by design
Developer data is often sensitive: API responses, tokens, customer records, internal configs. This CSV to TOON processes everything locally in your browser tab. There is no server round-trip, no logging and no storage of your input.
Frequently asked questions
Is this CSV to TOON free?
Yes. This CSV to TOON is completely free to use with no sign-up, no limits and no ads inside the tool.
Is my data uploaded to a server?
No. The CSV to TOON runs entirely in your browser using JavaScript. Nothing you paste is sent to DevT Pro or any other server.
Does the CSV to TOON conversion lose data?
The first row is used as column names. Numbers and booleans are detected automatically, and dotted headers such as address.city are expanded back into nested objects.
Can I use the CSV to TOON offline?
Yes. CSV to TOON is also built into DevT Pro, a native app for Mac, Windows, iPad and Linux with 120+ developer tools that work fully offline. It is a $5.99 one-time purchase with no subscription.
