YAML Formatter

What is the Free YAML Formatter?

The free YAML Formatter validates and beautifies YAML files instantly in your browser. Paste your YAML into the Input textarea and the tool checks it for syntax errors using a full YAML parser — then re-formats it with consistent 2-space indentation and clean structure in the Output panel. Whether you're working with Docker Compose files, Kubernetes manifests, GitHub Actions workflows, or Ansible playbooks, this free tool catches errors before they break your build.

• → Validate and format Docker Compose and Kubernetes YAML manifests
• → Check GitHub Actions, GitLab CI, or Bitbucket Pipelines workflow files for errors
• → Clean up YAML configuration files for Ansible, Helm, or Terraform
• → Fix indentation errors in YAML that cause silent failures at runtime
• → Inspect and reformat OpenAPI (Swagger) specs written in YAML format

How to Use the Free YAML Formatter

1. 1 Paste your YAML content into the Input textarea.
2. 2 Switch between Format mode (re-indent and normalise spacing) and Validate mode (check for errors without changing the content) using the toggle.
3. 3 If there are syntax errors, a red error message shows the line number and a description of the problem.
4. 4 If valid, the formatted output appears in the Output panel with consistent 2-space indentation.
5. 5 Click Copy to copy the cleaned YAML to your clipboard.

Key Features

• ✅
  Full YAML parsing

  Uses a complete YAML parser — catches indentation errors, tab characters, duplicate keys, and invalid values.
• 🖊️
  Consistent formatting

  Re-indents with 2 spaces and normalises structure for readability.
• ⚡
  Instant feedback

  Errors are shown immediately as you type or paste.
• 🔒
  Private processing

  Your YAML never leaves your browser — safe for API keys, secrets, and private config files.
• 🆓
  No upload required

  Paste directly — no file upload, no size limits, no account needed.

Example Usage

name: my-app
version: "1.0"
services:
  - web
  - db

name: my-app
version: "1.0"
services:
  - web
  - db

Frequently Asked Questions about the Free YAML Formatter

What is the free YAML Formatter?

Format and validate YAML files with clear syntax error reporting.

Is the YAML Formatter free to use?

Yes, the YAML Formatter is completely free. No account, subscription, or signup is required — ever.

Does my data get uploaded anywhere?

No. The YAML Formatter runs entirely in your browser. Your data is never sent to any server.

Does it work offline?

Yes. Once the page has loaded, the tool works without an internet connection.

Which browsers are supported?

All modern browsers — Chrome, Firefox, Safari, and Edge. No plugins or extensions required.

Why does my YAML fail when I use tabs?

YAML strictly prohibits tab characters for indentation — only spaces are allowed. This is the most common cause of YAML parse errors. Replace all tabs with spaces (2 or 4) and the error will resolve. Most code editors have a "Convert Indentation to Spaces" option in their settings.

Can I use this to validate Kubernetes or Docker Compose files?

Yes — this tool validates standard YAML syntax and will catch indentation errors, duplicate keys, and invalid characters. Note that it does not validate Kubernetes schema rules (invalid field names, wrong value types per spec) — only the underlying YAML structure. Use kubectl --dry-run for full schema validation.

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