JSON to TOML Converter

Convert JSON → TOML format in seconds.

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JSON Input

TOML Output

About JSON (JavaScript Object Notation)

JSON is a lightweight data-interchange format that is easy for humans to read and write, and easy for machines to parse and generate. Despite its name suggesting a connection to JavaScript, JSON is language-independent and is used across many programming languages.

JSON is built on two structures: a collection of name/value pairs (similar to objects in various languages) and an ordered list of values (similar to arrays). Its simplicity and widespread support make it ideal for web APIs and data exchange.

Example:

{
  "title": "TOML Example",
  "owner": {
    "name": "Tom Preston-Werner",
    "organization": "GitHub"
  },
  "database": {
    "server": "192.168.1.1",
    "ports": [8001, 8001, 8002],
    "connection_max": 5000,
    "enabled": true
  }
}

About TOML (Tom's Obvious, Minimal Language)

TOML is a minimal configuration file format that's easy to read due to obvious semantics. TOML is designed to map unambiguously to a hash table and should be easy to parse into data structures in various languages.

TOML aims to be a minimal configuration file format that's easy to read and write. It's used by many popular tools and projects including Rust's Cargo, Python's Poetry, Hugo, and more. TOML supports comments, nested tables, and various data types including strings, integers, floats, booleans, dates, arrays, and inline tables.

Example (from above JSON):

title = "TOML Example"

[owner]
name = "Tom Preston-Werner"
organization = "GitHub"

[database]
server = "192.168.1.1"
ports = [ 8001, 8001, 8002 ]
connection_max = 5000
enabled = true

How to Use This Converter

Enter JSON Data: Paste or type your JSON data into the input text area, or upload a JSON file. Make sure your JSON is properly formatted with correct brackets and quotes.
Convert: Click the "Convert" button to process your data.
View Result: The converted TOML data will appear in the output area.
Copy or Download: Use the "Copy" button to copy the result to your clipboard, or "Download" to save it as a TOML file.

Why Convert JSON to TOML?

Configuration Files

TOML is specifically designed for configuration files, offering better readability and maintainability than JSON.

Comments Support

Unlike JSON, TOML supports comments, making it easier to document your configuration directly in the file.

Modern Tooling

Popular tools like Cargo, Poetry, and Hugo use TOML for their configuration files.

Key Benefits of TOML

Human-readable: Clean, obvious syntax that's easy to understand at a glance
Comments support: Add explanatory comments directly in your configuration files
Unambiguous: TOML maps clearly to hash tables without confusion
Date-time support: Native support for dates and times in ISO 8601 format
Type-safe: Clear distinction between strings, numbers, booleans, and arrays
Growing ecosystem: Used by Rust Cargo, Python Poetry, Hugo, and many other popular tools

Common JSON to TOML Use Cases

Application Configuration

Convert JSON configs to TOML for:

Rust projects (Cargo.toml)
Python projects (pyproject.toml)
Static site generators (Hugo)

Configuration Migration

Convert existing JSON configs to TOML for:

Better readability
Comment documentation
Standardization across projects

TOML vs JSON for Configuration

Feature	TOML	JSON
Comments	Yes	No
Readability	High	Medium
Date/Time Types	Native support	String only
Trailing Commas	Not required	Causes errors
Use Case	Configuration files	Data exchange, APIs