Validate YAML Online.
Paste, upload, or write YAML. Validate against 11 configuration schemas, entirely in your browser.
What is YAML Validator?
A fast, browser-based online YAML validator for checking syntax and validating YAML files against schemas. Supports schema validation for Kubernetes, Docker Compose, GitHub Actions, and 8 more configuration formats. No server, no signup — all YAML validation happens locally in your browser.
YAML (YAML Ain't Markup Language) is widely used for configuration files across DevOps tools, cloud platforms, and CI/CD pipelines. A single indentation error or missing field can break a deployment. This validator catches syntax errors instantly and checks your configuration against official JSON Schemas — so you find problems before kubectl apply, docker compose up, or your CI pipeline runs.
Use it directly at yamlvalidator.dev, or install the Chrome extension for validation on GitHub, raw YAML files, and a quick-access popup editor.
11 Supported Schemas
YAML schema validation with auto-detection that identifies your YAML format from content patterns.
| Schema | Version | Auto-detection |
|---|---|---|
| Kubernetes | v1.29 | apiVersion + kind fields |
| Docker Compose | v2.29 | services + image/build |
| GitHub Actions | workflow | on + jobs fields |
| GitLab CI | latest | stages + script fields |
| CircleCI | v2.1 | version + jobs/workflows |
| Azure Pipelines | v1 | trigger + pool fields |
| Bitbucket Pipelines | pipes | pipelines field |
| Ansible | 2.x | hosts + tasks fields |
| Helm Chart | v2 | apiVersion + type chart |
| OpenAPI | 3.0 | openapi + paths fields |
| Swagger | 2.0 | swagger + paths fields |
Kubernetes v1.29 — Validate Deployment, Service, Pod, ConfigMap, Ingress, StatefulSet, DaemonSet, CronJob, and 50+ resource types. Catches missing required fields like selector and template before you run kubectl apply.
Docker Compose v2.29 — Check your docker-compose.yml for valid service definitions, port mappings, volume mounts, and network configurations. Prevents docker compose up failures.
CI/CD Pipelines — Validate GitHub Actions workflows, GitLab CI pipelines, CircleCI configs, Azure Pipelines, and Bitbucket Pipelines. Catch job dependency errors, invalid step definitions, and missing triggers before pushing.
API Specifications — Check OpenAPI 3.0 and Swagger 2.0 definitions for valid paths, schemas, and response definitions. Ensure your API documentation matches the spec.
Infrastructure as Code — Validate Ansible playbooks (hosts, tasks, handlers) and Helm Chart definitions (Chart.yaml metadata, dependencies).
Built for developers
Instant YAML Validation
Click validate or press Ctrl+Enter. Results in milliseconds, entirely client-side. Validate YAML files without sending data anywhere.
Schema Auto-Detection
Detects Kubernetes, Docker Compose, GitHub Actions, and more from content patterns. The YAML validator picks the right schema automatically.
Open & Save Files
Open YAML files from your computer, edit in-browser, and download when done. A complete online YAML file validator workflow.
Share via URL
Compressed sharing with no backend. Send YAML snippets to your team with a single link.
Multi-Document YAML
Full support for YAML files with multiple documents separated by ---. Validate all documents at once.
Dark & Light Themes
Easy on the eyes at any hour. The YAML validator remembers your theme preference.
Three steps
Paste or upload
Type YAML directly in the editor, paste from clipboard, or open a .yml file from your computer.
Pick a schema
Let auto-detection choose, or select from 11 built-in configuration schemas for YAML validation.
Validate & fix
See errors with line numbers and contextual hints. Fix issues and re-validate your YAML file until clean.
Questions
Is my YAML data sent to a server?
No. All parsing and validation happens entirely in your browser. Your data never leaves your machine.
What YAML versions are supported?
YAML 1.2 via js-yaml, with full support for anchors, aliases, multi-document files, and all standard data types.
Which schemas are supported for YAML validation?
11 built-in schemas: Kubernetes, Docker Compose, GitHub Actions, GitLab CI, CircleCI, Azure Pipelines, Bitbucket Pipelines, Ansible, Helm Chart, OpenAPI 3.0, and Swagger 2.0. Auto-detection identifies the right schema from your YAML content.
Is there a browser extension?
Yes. YAML Validator is available as a Chrome Extension and Firefox Add-on, adding validation, formatting, and code folding directly in your browser — including on GitHub YAML files.
How do I validate a Kubernetes YAML file?
Paste your Kubernetes manifest or open the .yaml file using the Open button. The validator auto-detects Kubernetes from the apiVersion and kind fields and validates against the official Kubernetes v1.29 JSON Schema, checking for missing required fields, invalid property values, and structural errors.
Can I validate multi-document YAML files?
Yes. Files with multiple documents separated by --- are fully supported. Each document is parsed and validated independently, with errors reported per document and line numbers mapped correctly.
How does YAML sharing work?
Click the Share button to compress your YAML content and copy a URL to your clipboard. The recipient opens the link at yamlvalidator.dev and sees the YAML pre-loaded in the editor. No account or backend needed — the content is encoded directly in the URL.
Take it with you.
Validate YAML everywhere with the browser extension.