TOML to JSON Converter

TOML is the configuration format of choice for many modern tools — Rust projects, Python packaging, static site generators — because it is explicit, readable and hard to get subtly wrong. But when a TOML file needs to feed a JSON-based system, or you need to inspect its structure programmatically, a conversion is the fastest route. This converter parses the TOML constructs used in everyday configuration — sections and subsections, key-value pairs, strings, integers, floats, booleans, arrays and datetimes as strings — and produces clean JSON with the same nesting. It runs entirely in your browser, so private configuration never leaves your device. It is a focused parser for common TOML, not a complete specification implementation: exotic features such as inline tables with complex nesting and multi-line strings are handled where practical, and the guide notes the scope honestly. For everyday config files, it converts accurately in one paste.

Quick Answer: Paste TOML configuration and get the equivalent JSON, with sections nested and values typed as strings, numbers, booleans or arrays.

Free Online Tool

TOML configuration
[server]<br /> host = “example.com”<br /> port = 8080<br /> tls = true<br /> tags = [“web”, “api”]

JSON output

How to Use the TOML to JSON Converter

Paste your TOML configuration into the input box.
Press Convert to JSON and read the result.
Check that sections became nested objects and values kept their types.
If an error is reported, check the line it names for a syntax problem.
Copy the JSON into your code, test or migration script.

Key Features

Sections and dotted subsections become nested objects
Strings, integers, floats, booleans and arrays typed correctly
Comments and blank lines ignored, as TOML intends
Clear errors naming the offending line
Free, instant and entirely in your browser

Best Practices and Tips

Keep section headers in one place per file: duplicate sections are an error in TOML, not a merge.
Quote strings that contain special characters; bare values are for numbers, booleans and dates only.
For large configs, convert one section at a time first to confirm the mapping matches your expectations.
Remember TOML is case-sensitive: Title and title are different keys, and JSON preserves that.
Validate the JSON output by parsing it in your own toolchain before relying on it in production.

Common Mistakes to Avoid

Defining the same section twice, which TOML forbids and this tool reports as an error.
Using unquoted strings for values with spaces or symbols, which breaks parsing.
Expecting TOML dates to become JSON dates: JSON has no date type, so they arrive as strings.
Mixing types in one array and assuming the converter will coerce them — it preserves each value type.

Frequently Asked Questions

What is TOML?

TOML — Tom Obvious Minimal Language — is a configuration file format designed to be obvious and unambiguous. It uses section headers in square brackets, key-value pairs, and a small set of value types, and it is widely used for project configuration.

How are TOML sections represented in JSON?

Each section header becomes a nested object: [server] gives a server object, and [server.tls] nests a tls object inside it. Keys inside a section become properties of that object.

What TOML features are supported?

Sections, dotted keys, strings (basic and literal), integers, floats, booleans, arrays of scalars, comments and blank lines. Complex inline tables and multi-line strings are supported in simple forms; very exotic TOML may need a full parser.

Why did my TOML fail to convert?

The usual causes are duplicate section headers, unquoted strings with special characters, or a missing equals sign. The error message names the line; fix that line and convert again.

Is the TOML to JSON converter free?

Yes — free, unlimited and no sign-up required.