Before building JSON to TOML Converter, we looked at how existing tools handle two real constraints of the TOML format itself, not just conversion mechanics.
TOML arrays can't mix types — most converters don't say so clearly
Research into existing JSON-to-TOML tools turned up a specific, well-documented limitation: a JSON array like [1, "two", true] mixes a number, a string, and a boolean, and TOML simply doesn't allow that in one array. Some converters handle this with a warning; others just produce output and leave you to discover the problem later. This tool stops and tells you exactly which field has the mixed array, so you can split it before it becomes a broken config file.
TOML has no null — so what happens to one?
The same research found that TOML has no native null type at all. Converters that don't account for this add a silent comment or just drop the field. This tool treats a null value as something it genuinely can't convert, and says so directly, rather than guessing what you meant.
Nested structure, done the TOML way
Nested JSON objects become proper [section] headers, and arrays of objects become [[array-of-table]] blocks — the standard TOML v1.0 conventions, generated live as you type.
