YAML Validator & Syntax Checker.
Inspect YAML syntax with exact line/column indicators, tab character detection, and actionable fix suggestions.
Syntax Diagnostic
Line 1, Col 1Invalid YAML Syntax
Instant YAML Syntax & Indentation Linting
YAML is notoriously strict about whitespace and indentation hierarchy. A single tab character or improper spacing under a dictionary key can cause production deployments to fail. Our online YAML validator and syntax checker analyzes your configuration according to YAML 1.2 rules.
Tab Detection
Flags forbidden tab characters (\t) and converts them to spaces with one click.
Line & Col Pointer
Pinpoints the exact character offset where parsing failed with a visual code snippet.
Multi-Doc Streams
Validates multi-document streams separated by --- dividers in one pass.
Frequently Asked Questions.
Everything you need to know about YAML to JSON conversion, syntax formatting, and privacy.
What does this YAML validator and syntax checker inspect?
It verifies your YAML against the official YAML 1.2 specification, identifying syntax errors, forbidden tab characters, irregular indentation, duplicate dictionary keys, unclosed quotation marks, and bad mapping colons.
How do line and column error pointers help fix YAML syntax?
When a syntax error occurs, our YAML validator isolates the exact line number and column position, providing a 3-line contextual code preview with a pointer (^) and actionable advice on how to fix the issue.
Does the YAML validator support multi-document files?
Yes! It validates all documents across "---" separators and reports per-document validation statuses.
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