How to convert JSON to TOML
- Paste a JSON object.
- Check the TOML on the right.
- Copy it or download it as a .toml file.
About this tool
TOML is the config format behind pyproject.toml and Cargo.toml. Paste a JSON object and get TOML with proper tables and arrays of tables. TOML has no null and needs an object at the top, so the page tells you exactly which value is the problem rather than guessing.
Common questions
Why does it say null is not allowed?
TOML has no null value. Remove that key or give it a value, and the page names the exact path.
Can the JSON be a list at the top?
No. A TOML file is a set of key and value pairs, so the top level must be an object.
Are nested objects supported?
Yes. They become [table] sections, and lists of objects become [[array]] sections.
Is it free to use?
Yes. There's no sign-up, and you can use it as often as you like.
Is my text uploaded anywhere?
No. This tool runs inside your browser, so what you enter stays on your device.
Do I need to install anything?
No. It works in your browser on a computer or a phone.