Developer Utilities · Free tool
YAML Linter
Lint and validate your YAML files instantly online with precise line and column error messages. Uses the same parser as GitHub Actions — free tool in your browser.
Updated June 2026
✓
Valid YAML
Pretty-printed
# Try editing this YAML — errors surface live
name: Free Tool Arena
tools: 838
categories:
- dev
- writing
- media
live: true
stats:
guides: 600
recent:
- { slug: dictionary, type: tool }
- { slug: geocoder, type: tool }
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What it does
Validate YAML files and surface precise line:col error locations. Uses the yaml package (the same one GitHub Actions, Sourcegraph, and others use under the hood) so errors match what your CI will complain about.
Valid input is also re-emitted in canonical form so you can spot subtle indentation drift.
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/yaml-linter" width="100%" height="720" frameborder="0" loading="lazy" title="YAML Linter" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Paste your YAML.
- Errors surface live as you type — no submit needed.
- Copy the canonical pretty-print if you want to normalize formatting.
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Learn more
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