YAML Validator / YAML Formatter
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What is a YAML Validator / YAML Formatter?
A YAML validator checks whether your YAML is syntactically valid and can be parsed correctly.
A YAML formatter makes YAML easier to read by applying consistent indentation and normalized structure.
How to use the YAML Validator / YAML Formatter
- Paste your YAML into the input field.
- Choose indentation size and optional key sorting.
- Click Format to pretty-print the YAML.
- Click Validate to only check syntax.
- Click Minify for compact YAML output.
Tips
- YAML is sensitive to indentation, so even small spacing issues can break parsing.
- Sorted keys can make configuration files easier to scan.
- The parsed JSON preview is useful for checking how YAML is interpreted.
- Use validation first if you only want to confirm syntax.
YAML checks before deploying configuration or data
Valid YAML can still produce unexpected values when parsers infer types, resolve aliases, merge mappings, or implement different specification versions.
Indentation and structure
Use spaces consistently and inspect nested mappings, sequences, multiline scalars, duplicate keys, and document separators.
Implicit types
Quote values that must remain strings, including dates, booleans, null-like words, numbers with leading zeros, and special notation.
Anchors and aliases
Review merges, reused nodes, alias expansion limits, and whether the destination parser supports the intended behavior.
Application validation
Validate against the expected schema and load with the same safe parser, version, and options used in production.
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