100% Free · Two-Way Conversion · Docker & K8s Templates

YAML Formatter & Validator

Clean up messy YAML manifests, convert between YAML and JSON with one click, and validate configuration syntax without uploading files.

YAML Formatter & JSON Converter

Format, validate, and convert YAML ↔ JSON seamlessly with zero server upload.

Templates:

Indent:

Input YAML

Converted JSON Valid Syntax

{
  "version": "3.8",
  "services": {
    "web": {
      "image": "nginx:alpine",
      "ports": [
        {
          "80": "80\""
        },
        {
          "443": "443\""
        }
      ],
      "environment": {
        "NODE_ENV": "production",
        "PORT": 80
      },
      "volumes": [
        {
          "./html": "/usr/share/nginx/html:ro"
        }
      ],
      "restart": "always"
    },
    "api": {
      "build": {
        "context": "./backend",
        "dockerfile": "Dockerfile"
      },
      "environment": {
        "DATABASE_URL": "postgresql://user:secret@db:5432/appdb"
      },
      "depends_on": [
        "db"
      ]
    },
    "db": {
      "image": "postgres:15-alpine",
      "environment": {
        "POSTGRES_DB": "appdb",
        "POSTGRES_USER": "user",
        "POSTGRES_PASSWORD": "secret"
      },
      "volumes": [
        {
          "pgdata": "/var/lib/postgresql/data"
        }
      ]
    }
  },
  "volumes": {
    "pgdata": {}
  }
}

Why Developers Use ToolHub YAML Formatter

Two-Way Bi-directional Conversion

YAML ⇄ JSON seamlessly

Switch direction instantly to convert Docker Compose, Kubernetes manifests, or CloudFormation templates between YAML and JSON.

Configurable Indentation

Strict 2-space or 4-space rules

YAML indentation is whitespace-sensitive. ToolHub standardizes spacing to prevent indentation mismatch errors.

Built-In DevOps Templates

Docker, Kubernetes & GitHub Actions

Load sample templates for quick scaffolding or compare your custom configs against verified standard syntaxes.

Frequently Asked Questions

Why does YAML not allow tab characters for indentation?

The official YAML specification forbids tabs for indentation because different text editors and systems render tab widths inconsistently (e.g. 2, 4, or 8 spaces), which can alter the parsed document structure.

Is YAML a superset of JSON?

Yes! In YAML 1.2, every valid JSON document is also valid YAML. This tool allows seamless translation between both data formats.

Are comments preserved when converting to JSON?

JSON does not officially support comments, so converting YAML to JSON strips comment lines. Converting JSON back to clean YAML produces formatted key-value pairs.