TOML Formatter & Validator

About the TOML Formatter & Validator

We built this tool to provide a simple, fast, and reliable way to work with TOML (Tom's Obvious, Minimal Language). TOML is a popular configuration file format that is designed to be easy to read due to its clear semantics. While it's human-friendly, it's easy to make a small syntax mistake that can break an application. Our tool solves this by both validating and formatting your TOML code in real-time.

What makes this tool the best for the job is its instant feedback. As you type, it continuously checks your syntax. If it finds an error, it tells you exactly what's wrong and on which line. If your code is valid, it automatically pretty-prints it in the output box with standardized indentation and spacing. The entire process happens securely in your browser, so your configuration data is never uploaded to our servers.

How to Use the Tool

• Paste your TOML code into the "Input TOML" editor on the left.
• If your TOML is valid, a clean, formatted version will instantly appear in the "Formatted & Validated TOML" box on the right, and a "Valid TOML" message will appear below.
• If there is a syntax error in your input, the output will remain empty, and a detailed error message will appear below, telling you what's wrong and where.
• Use the buttons to copy the formatted output, download it as a `.toml` file, or start over.

Frequently Asked Questions

What is TOML?

TOML stands for Tom's Obvious, Minimal Language. It's a configuration file format designed to be easy to read and write. It uses a clear structure of `key = "value"` pairs, `[sections]`, and `[[arrays of tables]]` to represent data hierarchies.

Why would I need to format or validate TOML?

Formatting keeps your configuration files consistent and readable, which is especially important when working in a team. Validation is crucial because a single syntax error, like a missing quote or an incorrect date format, can prevent an application from starting. This tool helps you catch those errors before they cause problems.

How does the validation work?

The tool uses a powerful open-source TOML parser that strictly follows the official TOML specification. When you input text, the tool attempts to parse it. If the parsing is successful, the TOML is valid. If it fails, the parser provides a detailed error message, which we display to help you fix the issue.

Does this tool support the latest TOML specification?

Yes. The library we use is kept up-to-date with the latest stable version of the TOML specification (v1.0.0), so it correctly handles all standard TOML features, including inline tables, multi-line strings, and date-time formats.

Is my configuration data private?

Yes, absolutely. All parsing, validation, and formatting happen directly in your web browser. Your data is never sent to our servers, making it a completely secure tool for working with sensitive configuration files.