TOML to JSON Converter
Convert TOML configuration into JSON online. Paste content from Cargo.toml, pyproject.toml or any other TOML file and get the equivalent JSON text instantly, ready for tooling that only understands JSON.
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How to Use
- Paste or edit your TOML content in the input box (for example a Cargo.toml or pyproject.toml snippet)
- The converted JSON appears below in real time
- If the TOML is malformed, a specific parse error message is shown
Features
- Converts TOML tables, arrays and inline tables into the equivalent JSON structure
- Converts as you type, with no button to press
- Reports a clear error message when TOML parsing fails
Use Cases
Pre-converting TOML for JSON-only toolchains
When your environment cannot parse TOML directly, convert it to JSON first and process it from there.
Inspecting Cargo.toml or pyproject.toml structure
Turn a Rust or Python project's TOML configuration into a JSON tree that is easier to read at a glance.
Migrating configuration formats
Move a project's configuration from TOML to JSON without rewriting every key by hand.
Debugging how TOML is parsed
Verify what data structure a block of TOML actually produces so you can confirm the configuration matches your expectations.
FAQ
Which parts of the TOML syntax are supported?
Tables ([table]), arrays of tables ([[array]]), inline tables and the basic types (strings, numbers, booleans, dates) all convert correctly. Very exotic TOML extensions may not be fully supported.
Why am I getting a TOML parse error?
Almost always because the TOML itself is invalid, such as a duplicated table name or a malformed key/value pair. Check the syntax and try again; the error message points at the specific problem.
How are TOML date and time values represented in the JSON?
TOML date and date-time values are emitted as ISO 8601 formatted strings in the converted JSON.
Is my data uploaded to a server?
No. The conversion runs entirely in your browser and nothing you paste leaves your machine.