YAML Formatter and Validator
Format, validate, and minify YAML online. Fix indentation, inspect syntax issues, upload config files, and keep everything private in your browser.
Shortcuts: Ctrl/Cmd + Enter formats, Shift + Enter minifies. Upload a .yaml file or download the cleaned result when you are done.
Paste config files, Kubernetes manifests, CI workflows, Docker Compose files, or any YAML snippet.
YAML needs attention
How to use this YAML formatter
- Paste YAML into the input panel or upload a
.yamlor.ymlfile. - Choose 2-space or 4-space output depending on your team convention.
- Use Format to clean indentation, Minify for inline flow style, or Validate to check syntax only.
- Review the error panel if validation fails, then copy or download the cleaned output.
Why developers use a YAML beautifier
YAML shows up everywhere: Kubernetes manifests, Docker Compose files, CI pipelines, Helm values, Ansible playbooks, and app configuration. When indentation drifts or nested blocks become inconsistent, the file gets hard to review and easy to break.
A YAML formatter makes nesting obvious, reduces copy/paste mistakes, and helps teams spot structural issues before they reach production.
Common YAML mistakes this validator helps catch
- Tabs instead of spaces: YAML indentation should use spaces only.
- Uneven nesting: A single extra space can move a key into the wrong block.
- Broken inline objects: Flow mappings need commas between entries, such as
{name: Ada, role: admin}. - Malformed lists: Sequence items need a leading dash and consistent indentation.
- Dangling keys: A key ending with
:usually needs an indented value or nested section below it.
Where YAML formatting matters most
- Kubernetes: deployments, services, ConfigMaps, and Helm values files.
- CI/CD: GitHub Actions, GitLab CI, CircleCI, and Azure Pipelines.
- Infrastructure automation: Ansible playbooks, inventories, and role variables.
- App configuration: framework settings, static-site config, and local development stacks.
Does this tool send my YAML anywhere?
No. Everything runs locally in the browser with client-side JavaScript. That is useful when you are checking internal infrastructure config, deployment manifests, or other files that should not be uploaded to a third-party service.