TOML Validator / Formatter
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What is a TOML Validator / Formatter?
A TOML validator helps you check whether TOML configuration files are syntactically valid.
A TOML formatter makes configuration files easier to read and inspect. This is useful for apps, tooling, build systems, and config files.
How to use the TOML Validator / Formatter
- Paste your TOML into the input field.
- Click Validate to check syntax.
- Click Format to normalize and reprint the TOML.
- Use TOML → JSON if you want to inspect the parsed structure.
Tips
- TOML is commonly used for configuration files.
- Keys, tables, arrays, booleans, and numbers must follow TOML syntax rules.
- Converting TOML to JSON is useful for debugging config structure.
- Formatting makes large config files much easier to review.
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TOML checks before using a configuration file
Syntax validation should be followed by checks for table shape, value types, date semantics, and compatibility with the consuming library.
Tables and dotted keys
Check duplicate definitions, parent-child conflicts, arrays of tables, quoted keys, and unintended nesting from dotted names.
Value types
Confirm integers, floats, booleans, arrays, inline tables, multiline strings, and mixed-type restrictions match the application.
Dates and times
Distinguish local dates, local date-times, offset date-times, precision, and timezone assumptions before conversion.
Parser version
Load the file with the exact TOML implementation used by the application because feature and specification support can differ.
Privacy and usage
Built for quick checks without an account
Toolinix tools are designed for short developer tasks: paste a safe sample, inspect the result, copy what you need, and move on.
No login required
You can use the tools without creating an account, subscribing to a newsletter, or saving a workspace.
Local when possible
Formatters, generators, encoders, and text utilities generally run in your browser. Network diagnostics may need a server-assisted lookup to check public URLs, domains, or IPs.
Keep secrets out
Do not paste production passwords, private keys, access tokens, customer records, or regulated data into online tools unless your own security policy allows it.
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