Converters
JSON ↔ TOML Converter
Turn JSON configuration objects into TOML tables or TOML into JSON. Check object roots, null handling, number limits, and a nested service example.
About this tool
When to use it
Turn JSON configuration objects into TOML tables or TOML into JSON. Check object roots, null handling, number limits, and a nested service example.
How to use it
Choose JSON to TOML for a generated configuration object that must be saved as a TOML file. Choose TOML to JSON to inspect settings in a JSON-based API or comparison tool. Switching direction resets the workspace to an example. Convert, review the table structure, and use Copy, Share, or Download to transfer the result.
Guide updated . Examples checked against this implementation.
Worked examples
JSON to TOML: nested settings
Input
{"service":{"port":3010}}Expected output
[service]
port = 3_010
The service object becomes a table. Numeric separators are serializer formatting, not a change to the port number.
TOML to JSON: inspect a table
Input
[service]
port = 3010Expected output
{
"service": {
"port": 3010
}
}The table becomes a nested object. The JSON output uses two-space indentation and contains values rather than TOML comments.
Errors and unsupported input
{"service":{"token":null}}Decide whether your application expects an omitted field or a replacement value. TOML cannot represent null; conversion rejects the document instead of dropping that property.
value = infJSON cannot represent infinity or NaN. Change the TOML value to a finite number or a quoted string if your receiving system accepts it.
Continue this workflow
- JSON Diff: Compare the converted object with your expected configuration.
- YAML ↔ TOML Converter: Convert directly between TOML and YAML for a YAML-based deployment configuration.
Format references
Questions
Frequently asked questions
Why must JSON start with an object?
A TOML document starts with a table of named keys. Wrap an array in a meaningful property only when the receiving application expects that shape.
Will TOML comments appear in JSON?
No. JSON output contains parsed values. Store explanatory comments separately or retain the original TOML file.