Convert TOML config files to pretty JSON and JSON back to TOML, with tables, arrays of tables and dates. Parse errors show the line number, entirely in your browser.
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- Runs entirely in your browser — your data is never sent to a server
- Handles tables, arrays of tables, inline tables and dates
- Parse errors point to the exact line
How it works
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1
Paste or enter the value you want to convert.
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2
Conversion happens instantly as you type.
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3
Review the result in the target format.
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4
Copy the result to your clipboard.
Why use this tool
Every dev utility, one place
Format, convert, encode, decode, and generate — no more juggling ten tabs.
100% private, always
Every tool runs in your browser — your code and data are never sent anywhere.
Works on any device
Runs on Windows, Mac, Linux, iOS, and Android — nothing to install.
Instant results
No queues, no build step — results update as you type.
Built to handle real data
Full Unicode support and RFC-compliant parsing, edge cases included.
Free, always
Free to use, with no rate limits, sign-up, or trial period.
Frequently asked questions
JSON has no date type, so offset date-times, local date-times, dates and times become ISO 8601 strings. When converting back, strings in those formats are written as TOML dates again.
TOML has no null value and a TOML document is always a table, so the JSON root must be an object and must not contain null.
A JSON array whose items are all objects becomes a [[name]] array of tables; other arrays stay inline.
No. Conversion happens entirely in your browser.
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