Convert JSON to TOML online — Cargo.toml & pyproject.toml
Paste JSON from APIs or exporters and preview TOML for Rust, Python and DevOps configs. Everything stays in your browser.
Developer notes
• JSON must parse cleanly first. • Nested objects map to TOML tables. • Arrays become TOML arrays of inline tables or values as supported by the emitter.
When teams pick this route
• Bootstrap Cargo.toml from JSON exporters. • Migrate API config JSON into pyproject.toml fragments. • Quick previews before committing TOML edits.
About these options
CSV exports: choose a delimiter (Auto follows locale — semicolon on /fr), RFC-minimal vs always-quoted fields, line endings, and whether to emit a header row. CSV imports: delimiter + whether row 1 holds column names (Auto delimiter follows locale only for convenience). JSON output (XML, YAML, or CSV sources): indentation (including compact one-line) and optional recursive key sort. JSON → XML: toggle pretty-printing and indent width. YAML output: indent width, readable vs tighter layout, and deterministic string quoting (there is no source YAML file to “preserve”). XML comments are not represented in the intermediate JSON tree.
Worked example
Package metadata
Sample input
Sample output
Dependencies map
Sample input
Sample output
Navigate related tools
Validate JSON with the JSON validator, minify configs via TOML minifier, or round-trip with TOML → JSON.
JSON → TOML FAQ
Privacy-first conversion
Key order?
Insertion order from JSON is preserved when stringifying to TOML.
Comments in output?
Generated TOML has no comments — add them manually after conversion.
Server uploads?
No — FastMinify never receives clipboard content.
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