TOML to JSON Converter
Bidirectional TOML ↔ JSON conversion in your browser.
What it's for
Convert config files effortlessly
DevOps compatible
Convert between TOML and JSON for CI/CD pipelines, Terraform, Ansible, and modern configuration tools.
100% private
Your config files — which may contain sensitive data — never leave your browser.
Types preserved
Integers, floats, booleans, dates, and strings are correctly mapped between both formats.
Instant
Conversion happens in real time as you type. No waiting, no server submissions.
How it works
Three steps, no hassle
Choose conversion direction
Select whether you want to convert from TOML to JSON or from JSON to TOML using the toggle at the top.
Paste or type your content
Enter your TOML or JSON content in the input area. The result appears in real time in the output panel.
Copy or download
Copy the converted file to clipboard or download it directly as .toml or .json as needed.
FAQ
Got questions?
TOML (Tom's Obvious Minimal Language) is a configuration file format designed by Tom Preston-Werner in 2013. It was created to be easy for humans to read and write, with clear semantics that map unambiguously to a hash table. Its name is a nod to its creator and its philosophy of simplicity.
JSON is great for structured data but hard to write manually due to the abundance of braces and quotes. YAML is readable but its indentation sensitivity causes frequent production errors. TOML combines human readability with unambiguous syntax: sections are defined with [table], arrays with [[table]], and data types are explicit.
TOML is the official configuration format of the Rust ecosystem (Cargo.toml for package dependencies), Python (pyproject.toml for project configuration per PEP 518 and PEP 621), and the Hugo static site generator. It is also used in tools like the Starship prompt and various Go projects.
Yes. You can convert TOML to JSON for use with APIs or tools that only accept JSON, and also JSON to TOML to generate more readable configuration files. The tool preserves data structure and types during conversion.
Nested TOML tables ([table.subtable]) are converted to nested JSON objects. Arrays of tables ([[table]]) are converted to arrays of objects in JSON. In the reverse direction, nested JSON objects are converted to TOML tables using dot notation or sections depending on depth.
TOML to JSON: history, ecosystem, and when to use each format
TOML was created by Tom Preston-Werner (GitHub co-founder) in 2013 as a response to frustration with existing configuration file formats. YAML was too complex, JSON did not support comments and had limited data types, and INI lacked standardization. TOML 1.0.0 was published in January 2021 after years of iteration, consolidating its specification and guaranteeing stability for adopting ecosystems.
TOML's adoption in Rust through Cargo.toml was decisive for its popularization. The Python ecosystem also formally adopted it with PEP 518 (2016) and PEP 621 (2020), making pyproject.toml the standard for modern Python project configuration, replacing setup.py and setup.cfg. Tools like Poetry, Flit, and PDM use TOML extensively.
The need to convert between TOML and JSON arises frequently in DevOps pipelines: many REST APIs and CLI tools only accept JSON, but developers prefer to maintain their configurations in TOML for readability. Having a fast browser-based conversion tool eliminates the need to install Python or Node.js dependencies just to transform a configuration file.