TOML Formatter

Features

What is TOML?

TOML (Tom's Obvious, Minimal Language) is a configuration file format designed to be easy to read and write due to obvious semantics. Created by Tom Preston-Werner (co-founder of GitHub), TOML aims to be a minimal configuration file format that's easy to parse and unambiguous in its meaning.

TOML is widely used in modern development tools, particularly in the Rust ecosystem (Cargo.toml) and Python packaging (pyproject.toml). Its clear syntax makes it more readable than JSON for configuration files while being more structured than YAML. TOML files use the .toml extension and are human-friendly while remaining machine-parseable.

Why Use TOML?

• Readable: Clear, obvious syntax that's easy for humans to read and write
• Unambiguous: No confusion about data types or structure
• Minimal: Simple syntax without unnecessary complexity
• Structured: Supports nested tables and arrays
• Type-safe: Clear distinction between strings, numbers, booleans, dates
• Popular: Used by Rust, Python, and many modern tools

TOML Syntax Basics

TOML uses key-value pairs, tables (sections), and arrays:

• Key-Value: key = "value"
• Tables: [section] defines a new section
• Nested Tables: [parent.child] for hierarchy
• Arrays: array = [1, 2, 3]
• Strings: "basic" or 'literal' or """multi-line"""
• Numbers: 42, 3.14, 1e6
• Booleans: true or false
• Dates: 1979-05-27T07:32:00Z