Developer Utilities · Free tool
YAML Formatter
Format and validate YAML data instantly in your browser. Catches tab errors and bad anchors while pretty-printing — a free online tool with no downloads needed.
Expected "key: value" at: "# project config"
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What it does
Paste YAML and get it validated, indented, and pretty-printed. Catches common mistakes — accidental tabs, mis-indented lists, trailing colons — with line-specific error messages. All parsing happens in your browser, so config files with secrets never leave the page.
Convert to JSON with YAML JSON converter, compare with JSON diff checker, or inspect a full JSON payload using JSON formatter.
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-formatter" width="100%" height="720" frameborder="0" loading="lazy" title="YAML Formatter" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Paste YAML into the input box.
- Click Format — invalid YAML shows a line-anchored error.
- Pick 2 or 4-space indent.
- Copy the formatted output.
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