Yaml Viewer

YAML relies entirely on indentation for structure, so a misplaced space can silently change meaning or break a deployment. The YAML formatter re-indents your document consistently, validates that it parses and makes nested structures easy to read. It is handy for Kubernetes manifests, Docker Compose files, GitHub Actions workflows, Helm values and Ansible playbooks.

How to use it

1. Paste YAML.
2. Fix any reported syntax errors.
3. Copy the formatted output.

Example

Input with inconsistent indentation and flow style:

services:
    web:
       image: nginx:1.27
       ports: ['80:80']
    db: {image: postgres:16, environment: {POSTGRES_PASSWORD: example}}

Formatted output:

services:
  web:
    image: nginx:1.27
    ports:
      - '80:80'
  db:
    image: postgres:16
    environment:
      POSTGRES_PASSWORD: example

Common YAML errors

• Tabs: YAML forbids tab characters for indentation.
• Missing space after a colon: key:value is a string, not a mapping.
• Inconsistent indentation between sibling keys.
• Unquoted special values: 80:80 port mappings, yes/no, version numbers like 1.10 and values starting with *, & or @ should be quoted.
• Duplicate keys: many parsers silently keep only the last one.

Tips

• Use 2-space indentation, the de facto standard.
• Add yamllint to CI to catch problems before deployment.
• Comments are generally preserved only by formatters that work on the text; parse-and-dump formatting may drop them.