Developer Utilities · Free tool
TOML Linter
Check your Cargo.toml or pyproject.toml for syntax errors instantly using the trusted parser from Rust and Python tooling. Free online, no sign-up.
Updated June 2026
✓
Valid TOML
4 top-level keys parsed.
Re-emitted (canonical form)
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What it does
TOML linter / validator. Uses @iarna/toml — the same parser used by Cargo, pyproject.toml tooling, and most Rust/Python TOML consumers. Errors include line and column.
Valid TOML is re-emitted in canonical form so dotted-key shorthand vs explicit-table notation gets normalized.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/toml-linter" width="100%" height="720" frameborder="0" loading="lazy" title="TOML Linter" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Paste your TOML.
- Errors and the parsed structure update live.
- Use the canonical re-emit to normalize your file.
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