Validate YAML

Check YAML indentation, mappings, sequences, quotes, and nested structure with a YAML parser.

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ToolYAML Validator
Input
Output
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Preview

How it works

A YAML 1.2-compatible loader parses indentation, mappings, sequences, quoted scalars, anchors, and nested structures. Empty input is treated as a valid empty document.

  • A parser is necessary because YAML structure depends on indentation and quoting.
  • Empty YAML represents an empty document rather than a syntax error.

Worked example

Valid YAML
Validate a well-formed YAML document
Input
											name: my-service
version: 1.0
services:
  web:
    port: 8080
    host: localhost
Output
												Valid YAML

When to use this

Kubernetes manifests, CI configuration, and static-site data validate YAML.

Edge cases

  • Tabs used for indentation can fail where spaces form a valid block.
  • An unquoted colon followed by a space can start a mapping.
  • Unmatched quotes or brackets return a parser location.

References