JSON to TOML Converter

• Converts JSON objects to TOML tables and arrays with correct [section] and [[array]] syntax
• TOML is required by Cargo.toml (Rust), pyproject.toml (Python/PEP 518), Hugo (Go), and Netlify config
• JSON arrays map to TOML arrays, nested objects become [table] sections, arrays of objects become [[table]]
• Preserves data types: strings, integers, floats, booleans, and ISO 8601 datetime values
• Essential when migrating configuration between JSON-based APIs and TOML-based build tools

Use Cases

Frequently Asked Questions

How do I convert JSON to TOML format online?

Paste your JSON data into the input panel and the converter instantly generates valid TOML output with proper [table] sections, [[array of tables]] syntax, and correctly typed values. You can copy the result to clipboard or download it as a .toml file for direct use in your project.

Does this converter support TOML to JSON conversion too?

Yes. This is a bidirectional converter. Switch to TOML-to-JSON mode, paste your TOML content, and get properly formatted JSON output. This is useful for converting Cargo.toml or pyproject.toml files into JSON for API consumption or programmatic processing.

Can I use this for Cargo.toml and pyproject.toml files?

Yes. The converter generates valid TOML that works with Cargo (Rust package manager), pyproject.toml (Python PEP 518), Hugo site configs, Netlify deployment files, and any other tool that uses TOML v1.0 format. It correctly handles [dependencies], [[bin]], [tool.poetry], and other common TOML table patterns.

How does JSON map to TOML structure?

JSON objects become TOML tables with [section] headers. Nested objects use dotted paths like [parent.child]. JSON arrays of primitives become TOML arrays (values = [1, 2, 3]). JSON arrays of objects become TOML arrays of tables using [[double.bracket]] syntax. Strings, numbers, booleans, and null values are converted to their TOML equivalents.

Is my JSON or TOML data sent to a server during conversion?

No. All conversion processing runs entirely in your browser using client-side JavaScript. Your configuration data, API keys, secrets, and other sensitive content never leave your device. This makes the converter safe for use with private project configurations.

What TOML data types does the converter support?

The converter supports all TOML v1.0 data types: strings (basic and literal), integers, floats, booleans, ISO 8601 datetime values, arrays, inline tables, and standard tables. It correctly distinguishes between integer and float number types and preserves the semantic meaning of your data during conversion.

Is this JSON to TOML converter free to use?

Yes. This converter is 100% free with no signup, no account registration, and no usage limits. Convert as many JSON and TOML files as you need for your development workflow.