YAML Validator Online
Validate your YAML files instantly in the browser. Catch indentation errors, duplicate keys, and syntax problems before they cause deployment failures — all client-side.
YAML Validator & Formatter
Validate, format, beautify, and minify YAML documents instantly. Perfect for Kubernetes manifests, Docker Compose files, CI/CD configs, and more.
About YAML Formatting
YAML (YAML Ain't Markup Language) is a human-readable data serialization format widely used for configuration files in Kubernetes, Docker Compose, GitHub Actions, Ansible, and more.
Validation: Checks for correct YAML syntax including proper indentation, valid key-value pairs, correct use of colons and dashes, and proper quoting. Reports the exact line and column of errors.
Format: Parses and re-serializes your YAML with consistent indentation. Optionally sorts keys alphabetically for easier scanning and diff-friendly output.
Minify: Converts block-style YAML to compact flow style, reducing file size while preserving all data. Useful for embedding YAML in scripts or reducing payload size.
Everything runs in your browser — no data is sent over the network.
What is YAML validation?
YAML validation checks a document for syntax errors, indentation problems, duplicate keys, and structural issues. Because YAML is whitespace-sensitive, even a single misplaced space can break an entire configuration file. A YAML validator catches these issues immediately, saving time that would otherwise be spent debugging cryptic parser errors in production.
Common use cases
YAML validation is essential before deploying Kubernetes manifests, pushing CI/CD pipeline configs, or updating Docker Compose files. A single indentation error can cause a deployment failure or, worse, silently misconfigure a service. Validating YAML locally catches these issues before they reach production.
Frequently Asked Questions
What YAML errors does this validator catch?
The validator detects indentation errors, duplicate keys, invalid data types, incorrect multiline string syntax, improper list formatting, tab characters (which are not allowed in YAML), and other structural issues.
Can I validate Kubernetes YAML with this tool?
This tool validates YAML syntax and structure, which catches most common Kubernetes config errors. For schema-level validation (checking that fields match the Kubernetes API spec), you would additionally need a Kubernetes-specific linter.
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