TOML to JSON Converter

How to use TOML to JSON Converter

Three simple steps, with your content kept on your device.

Built for useful work

Fast, focused, and made to be clear on every screen.

Why convert TOML to JSON

TOML is designed for configuration files, while JSON is the interchange format used by APIs, build tools, and most programming languages. Converting TOML to JSON lets you take configuration written for one toolchain and feed it into another that expects JSON.

A TOML to JSON converter is especially useful in CI pipelines and container workflows, where configuration is authored in TOML but consumed by tools that read JSON. When a pipeline asks for a toml config to JSON step, the conversion is mechanical — using a converter guarantees a faithful result without retyping values.

How the converter works

To convert TOML online, paste your configuration into the editor and run the converter. Nested [table] sections become nested JSON objects, [[array of tables]] sections become arrays of objects, and inline tables, dotted keys, arrays, strings, numbers, booleans, and dates are all handled automatically.

The output uses clean two-space indentation with correct JSON escaping, so the result is ready to paste into a config file or save as a .json download for your application.

TOML types and JSON equivalents

TOML and JSON share most scalar types: strings, integers, floats, booleans, and arrays map directly. The interesting cases are TOML dates and times, which have no native JSON type, so offset date-times become ISO 8601 strings, and local dates and times become date or time strings.

Tables become objects and arrays of tables become arrays of objects, matching how most serializers represent TOML documents in JSON. Comments in the TOML source are not carried into the JSON output, since JSON has no comment syntax.

Common TOML pitfalls

The most common TOML mistakes are duplicate keys, mixing dotted keys with table headers for the same name, and using an inline table where a multi-line table is expected. The converter reports invalid TOML with the exact line and reason, so you can fix the source quickly.

String quoting is another frequent source of errors. TOML supports basic and literal strings with different escape rules, and the converter respects both, so single-quoted literal strings and double-quoted basic strings are handled correctly.

Privacy and locality

Configuration files often contain connection details, environment settings, or internal endpoints. Converting TOML to JSON in your browser keeps that data on your device — nothing is uploaded to a server, and there is no account or sign-up required.

The conversion runs entirely with client-side JavaScript, so it works offline once the page is loaded and handles your configuration as quickly as your browser can parse it.

Related data tools

Data conversion rarely stops at one format. The YAML Validator checks YAML syntax, the JSON to YAML Converter works in the opposite direction, and the XML to JSON Converter handles XML documents that carry the same data.

Once your data is in JSON, the JSON Validator checks syntax, the JSON Schema Validator checks it against a schema, and the JSON Formatter makes it readable for inspection.

TOML in real projects

TOML appears in many real toolchains: Python projects use it in pyproject.toml, Rust projects in Cargo.toml, and container tools in configuration files. When any of those tools needs JSON input, a converter produces it faithfully from the same source of truth.

Because the converter handles the full TOML 1.0 feature set — dotted keys, arrays of tables, inline tables, and the full range of scalar types — real-world configuration files convert without hand-editing.

Teams that keep configuration in TOML but ship JSON artifacts can now convert in the browser in seconds, with a copyable or downloadable result ready for the next step in the pipeline.

Frequently asked questions