JSON tools
Try tables, repeated server entries and a large identifier. Dates become strings; unsafe integers become strings by default.
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TOML to JSON is useful when a configuration file needs to feed an API, a fixture or a script that expects JSON. A section becomes an object, while double-bracket [[table]] headers become an ordered list of objects.
Before converting Cargo.toml to JSON, separate syntax from application meaning. This page maps data types; it does not decide whether a package manifest or deployment configuration contains the right fields.
TOML to JSON resolves table scope before writing braces. An item under [[servers]] stays in that array entry, and a quoted "api.version" remains a single key rather than an extra nested object.
The type preview distinguishes ordinary numbers, large integers written as strings, date strings and null replacements. You can spot a changed representation by its JSON Pointer without searching through a long output document.
The default writes integers outside ±9007199254740991 as decimal strings. Choose Reject if your receiving schema requires numbers and a changed type should stop the conversion. Integers beyond signed 64-bit range always fail.
NaN and infinity are valid TOML float values but are absent from JSON. Rejection is the default. The explicit null option also handles overflowing floats; the null count shows how many output values were replaced.
Automatic conversion waits 350 milliseconds. Disable it to use Convert or Ctrl/Cmd+Enter. Editing source or options immediately disables export. The preview shows 50 more nodes at a time, up to 500, while download includes the complete result.
Dotted keys and ordinary tables become nested objects. Arrays of tables retain item order and the scope of child sections. Empty tables remain {}, empty lists remain [], and lists containing multiple supported types stay mixed.
The parser reads every integer as BigInt before applying the selected policy. Decimal, hexadecimal, octal and binary input normalize to decimal output. Separators disappear; accepted large values retain their exact digits as strings.
Offset date-times retain the authored offset. Local date-times have no added zone; date-only and time-only values keep those forms. Output uses ISO strings with millisecond precision where there is a time; finer fractional seconds are truncated.
Syntax failures show the parser’s line and column and highlight the input line. Numeric policy failures identify a JSON Pointer instead. The preview escapes / as ~1 and ~ as ~0, so unusual property names remain unambiguous.
Ordinary [table] sections become objects; repeated [[table]] sections become arrays of objects. TOML to JSON preserves array order and attaches nested sections to the current parent item. A normal table does not become an array just because it contains several keys.
JSON has no native date value, so dates and times become strings. Local forms remain local and explicit offsets are retained. Times use milliseconds, so additional fractional digits are truncated. Check calendar validity separately because the parser can normalize some invalid dates.
The result is always JSON. Choose two spaces, four spaces or compact output; this changes whitespace, not the mapped values. Copy and download include all values even when the type table displays only the first 500 nodes.
This page rejects them by default, with a path identifying the first affected value. Choose the null policy only when null is acceptable to the receiving application. No value is removed from an array or object.
The error line and column refer to the TOML input, and the editor highlights that line. Policy errors instead report a JSON Pointer because the parser does not provide source positions for decoded values. After a failure, an earlier result remains unavailable for export.
Found a configuration with an unexpected result?
Use TOML to JSON to compare the example’s dates and identifier with the output types, then convert your own document.