Configuration made simple. Processing stays local.
JSON to TOML & TOML Formatter
Convert JSON to TOML, export TOML as JSON, or format and validate your configuration. No uploads or accounts.
Loading TOML parser…
All conversion happens in this tab. A pinned TOML parser loads from a CDN; your input is never sent to it. JSON transferred from the merger is stored temporarily in this tab and removed when loaded.
Convert JSON configuration to TOML
Paste a JSON object to generate TOML tables, arrays, and values automatically. Use TOML ➔ JSON for two-space-indented JSON, or TOML Formatter to validate and standardize an existing configuration file.
Rust Cargo.toml and Python pyproject.toml
Work with Cargo or Python project configurations without uploading them. This tool validates TOML syntax, not Cargo or Python packaging requirements. Check the generated configuration with your project’s own tooling.
Conversion details
TOML requires a top-level object and cannot represent null. Replace null values explicitly before converting. Unsafe JSON integers and TOML integers outside the JSON safe range are rejected on JSON export to avoid silent precision loss. TOML inf and nan cannot be exported as standard JSON.
The formatter parses and serializes TOML, so comments, original spacing, and key order are not preserved. TOML date and time values become strings in JSON. Formatting does not validate a configuration schema.
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