Convert JSON to TOML for config files
Paste JSON and get TOML — scalars, arrays and nested tables — ready for a Cargo, pyproject or app config. It converts in your browser (0 uploads, works offline).
How to use it
- Paste your input into the left pane.
- Choose any options shown above the panes.
- The result updates live on the right — Copy or Download it.
FAQ
How do I convert JSON to TOML for free?
Paste a JSON object on this page and it becomes TOML instantly in your browser, with no upload. Top-level keys become bare assignments and nested objects become [table] sections.
Why does it need a top-level object?
TOML documents are tables — a set of key/value pairs — so the root must be an object, not a bare array or value. The tool tells you clearly if the top level is not an object.
Is my JSON uploaded?
No. Conversion runs locally and nothing is stored; it works offline.
Which TOML shapes are supported?
Scalars, arrays of scalars and nested tables — the shapes real config files use. Arrays of tables and other exotic constructs are out of scope.
Limits
One-way JSON → TOML, covering scalars, scalar arrays and nested tables. Arrays-of-tables are not emitted.
Related
JSON to YAML and JSON to XML handle the other config formats.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.