JSON to TOML: convert JSON to typed TOML config
Convert JSON to TOML online — free, fast, browser-only. Uses the @iarna/toml reference implementation, preserves types (integers, floats, booleans, dates), and emits proper tables and inline arrays for Cargo.toml or pyproject.toml.
JSON in, TOML out
See exactly how JSON maps onto TOML — the converter on this page produces output identical to the example below.
{
"database": { "host": "localhost", "port": 5432, "enabled": true },
"servers": {
"alpha": { "ip": "10.0.0.1" },
"beta": { "ip": "10.0.0.2" }
}
}[database] host = "localhost" port = 5432 enabled = true [servers] [servers.alpha] ip = "10.0.0.1" [servers.beta] ip = "10.0.0.2"
What you'll use this for
Converting JSON to TOML is a daily task in API integration, config management, and data pipelines.
API integration
Generate Cargo.toml or pyproject.toml from JSON manifests.
Config migration
Move from JSON-based config to TOML for human-edited project files.
Data import
Bundle JSON metadata into TOML-consuming Rust or Python tools.
CI pipelines
Generate TOML configs from version-controlled JSON during builds.
How to convert JSON to TOML
Paste your JSON
Drop it into the left editor. The sample is loaded by default — clear it or click the wand to reload.
Click Convert
Or leave auto-convert on for live updates. Conversion runs entirely in your browser — no upload.
Copy or download
Copy to clipboard or save the output as config.toml.
Reverse if needed
Jump to the TOML to JSON converter for a round-trip check.
Frequently asked questions
Yes. TOML is strongly typed — integers, floats, booleans, strings, and dates remain distinct.
They become TOML tables ([section.subsection]) or inline tables for short objects.
Yes. No signup, no limits.
You'll see a clear parse error in the output panel.
Use the TOML to JSON converter for the opposite direction.
About JSON and TOML
TOML (Tom's Obvious Minimal Language) is a strongly-typed config format designed to be human-editable and unambiguous. It's the canonical format for Rust's Cargo.toml, Python's pyproject.toml, and many modern tools.
Common pitfalls
- Keys must be valid bare keys or quoted strings.
- Arrays of tables use the
[[name]]syntax — handled automatically. - Dates are ISO-8601; strings with newlines use triple-quoted literals.
- TOML cannot represent
null— null fields are omitted.