TOML Formatter

Validate TOML and emit a normalized version

Runs in your browserUtility01Formatters & Validators

What is TOML Formatter?

A TOML tool parses your configuration and reports syntax errors, then prints a normalized version with consistent formatting for table headers, arrays, and inline tables. It is commonly used to check Cargo.toml and pyproject.toml, and parsing runs locally in your browser.

How to use TOML Formatter

  1. 1Paste your TOML content.
  2. 2Valid input lists the top-level table names; invalid input shows the parse error.
  3. 3Replace the original file with the normalized output to keep formatting consistent across the team.

Frequently asked questions

What does TOML give me over YAML?+

Indentation carries no meaning in TOML, so you never hit the subtle YAML failures caused by the wrong number of spaces or a stray tab, and value types are more explicit. The trade-off is that deeply nested structures are more verbose than in YAML, which makes TOML a better fit for configuration than for data.

Why was my date field parsed as something other than a string?+

TOML has native date-time types, so a value like 2026-07-31T10:00:00Z is parsed as a timestamp rather than a string. Wrap it in quotes when you want it treated as text.

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