TOML to JSON Converter Online

TOML tables ([section]) become nested JSON objects. For example, [package] with name = "myapp" and version = "1.0" becomes {"package": {"name": "myapp", "version": "1.0"}}. Dotted keys like [database.primary] create nested objects: {"database": {"primary": {...}}}. This mapping preserves the hierarchical structure of your TOML configuration exactly.

TOML arrays of tables ([[array]]) are converted to JSON arrays of objects. Each [[array]] section becomes an element in the JSON array. For example, two [[products]] sections with different fields become [{"name": "Widget"}, {"name": "Gadget"}] under the "products" key. This is the correct semantic mapping that preserves TOML's intent.

No. TOML comments (# comment) are discarded during conversion because JSON does not have a comment syntax. The data values themselves are preserved exactly. If you need to keep comments as documentation, consider adding them as separate string fields in your JSON, or keep the original TOML as the source of truth.

TOML natively supports date, time, and date-time types. These are converted to ISO 8601 strings in JSON. For example, a TOML date 2024-01-15 becomes the string "2024-01-15", a TOML datetime 2024-01-15T10:30:00Z becomes "2024-01-15T10:30:00Z", and local times like 08:30:00 become "08:30:00". JSON does not have native date types, so string representation is the standard approach.

Yes. The converter handles TOML files of any reasonable size. Since all processing happens in your browser, performance depends on your device, but files up to several megabytes convert in under a second on modern hardware. For extremely large files, the parser streams the content efficiently.

TOML multiline basic strings (triple-quoted) and multiline literal strings are converted to regular JSON strings with newline characters (\n) embedded. TOML's line-ending backslash trimming is applied before conversion, so the JSON output reflects the actual string content as TOML intends it.

TOML is designed to be human-readable and writable, with support for comments, date types, and a cleaner syntax for nested structures. JSON is more universal and machine-readable, supported by virtually every programming language and API. TOML is preferred for config files that humans edit directly; JSON is preferred for data interchange and programmatic consumption. This converter bridges the gap between both worlds.

Yes! Use our JSON to TOML converter to go in the reverse direction. Note that round-tripping may not preserve comments or specific TOML formatting choices (like inline vs standard tables), but all data values will be preserved accurately.