ASAPUtils
What is a YAML Validator?
A YAML validator, sometimes called a YAML linter, parses your YAML text and checks it against the YAML specification. If there is a syntax error, it tells you exactly which line the problem is on and what type of error it is.
This is particularly important for configuration files where a single indentation mistake can cause a deployment to fail or an application to start with incorrect settings.
All validation runs locally in your browser. Nothing is uploaded anywhere.
How to Use
- Paste your YAML: Drop your YAML text into the editor.
- Read the error report: If there is a syntax error, the tool highlights the problematic line and shows a descriptive error message with the line number.
- Fix and revalidate: Correct the issue and the tool revalidates everything instantly.
Use Cases
Kubernetes manifests: A YAML parse error in a Kubernetes manifest will cause your apply command to fail with a cryptic error. Validating here first tells you exactly what is wrong and on which line.
GitHub Actions and GitLab CI: Pipeline YAML failures are expensive. You push, wait for the runner, then read a confusing error. Validate your workflow file here before pushing to catch indentation errors immediately.
Ansible playbooks: Ansible parses YAML at runtime. An invalid playbook may fail mid-run after already making changes to your servers. Validating the YAML before running prevents partial execution.
Docker Compose: Docker Compose will refuse to start if the configuration file has syntax errors. Paste it here first to confirm it is valid.
Why Use This
The validation runs entirely in your browser using a JavaScript YAML parsing library. Your config files often contain sensitive values like API keys, database credentials, or infrastructure details. Because this tool runs locally, your data never reaches an external server.
Validation is also instantaneous because there is no upload or network step involved.
Related tools
- YAML Formatter - Fix YAML indentation and formatting
- YAML Viewer - Explore YAML as a collapsible tree
- YAML to JSON - Convert YAML to JSON