TOML to JSON Converter

Input TOML

or drop a file anywhere

Output JSON

Your JSON appears here as you type.

Paste data to see token savings

Convert TOML to JSON for web applications or when JSON is required.

Example: TOML input and real JSON output

The output below was generated by the same conversion code the converter uses, run on this sample when the page was built.

TOML input (155 characters)

[package]
name = "invoice-tool"
version = "0.3.2"
edition = "2021"

[dependencies]
serde = "1.0"
tokio = "1.40"

[profile.release]
lto = true
opt-level = 3

JSON output (244 characters)

{
  "package": {
    "name": "invoice-tool",
    "version": "0.3.2",
    "edition": "2021"
  },
  "dependencies": {
    "serde": "1.0",
    "tokio": "1.40"
  },
  "profile": {
    "release": {
      "lto": true,
      "opt-level": 3
    }
  }
}

JSON output is 57% larger than the TOML input. The same data is 165 characters as minified JSON and 244 as pretty-printed JSON. Sizes are character counts, not tokens: token counts depend on the model's tokenizer (see the tokenizer comparison).

TOML to JSON: what changes

Nested tables such as [profile.release] become nested objects. Dotted keys and inline tables produce the same JSON shape as full table headers.
Reading TOML: A TOML document always parses to a table (an object), never a bare array. Datetimes are a TOML-native type and come out as ISO 8601 strings.
Writing JSON: Output is pretty-printed with your chosen indentation. JSON is the safest target when the data goes into code, an API, or another tool.

About TOML

TOML is a config file format with explicit types. It's the official format for Python's pyproject.toml and Cargo's Cargo.toml.

✓Explicit types
✓Standard in Python/Rust
✓Unambiguous
✓Easy to parse

Full TOML Documentation →

About JSON

JavaScript Object Notation is the most widely used data interchange format. Lightweight, easy to parse, and supported by every programming language.

✓Universal compatibility
✓Easy to parse
✓Great for APIs
✓Native in JavaScript

Full JSON Documentation →

Why Convert TOML to JSON?

Use JSON when you need maximum compatibility with other systems, APIs, or programming languages. It's the de facto standard for web APIs and data exchange.

TOML to JSON: Frequently Asked Questions

How do I convert TOML to JSON?

Paste your TOML into the editor on json2toon.co. The tool detects the input and produces JSON instantly, then you copy the result. Conversion runs entirely in your browser, so nothing is uploaded to a server.

Is the TOML to JSON converter free?

Yes. Converting TOML to JSON on json2toon.co is free with no account, signup, or usage limit. A free public API is also available for automated, programmatic conversion.

Why convert TOML to JSON?

Convert TOML to JSON for web applications or when JSON is required.

What should I watch out for when converting TOML to JSON?

Nested tables such as [profile.release] become nested objects. Dotted keys and inline tables produce the same JSON shape as full table headers.

Is my data safe when I convert TOML to JSON?

Yes. The TOML to JSON conversion happens client-side in your browser. Your source data stays on your device and is never sent to or stored on a server, which makes it safe for private or sensitive payloads.