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YAML Validator

Validate YAML for common syntax and indentation issues.

Tool

Use this YAML validator to check for common syntax problems such as tabs, broken indentation, malformed list items, and quote issues. It is useful for config files, CI pipelines, deployment manifests, and any workflow where invalid YAML can break automation or deployment.

About this tool

Use this YAML validator to check for common syntax problems such as tabs, broken indentation, malformed list items, and quote issues. It is useful for config files, CI pipelines, deployment manifests, and any workflow where invalid YAML can break automation or deployment.

Use yaml validator when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.

Learn more

Why use this tool

How to use

  1. Paste the YAML into the input box.
  2. Run the validator to check the syntax.
  3. Review whether the YAML is valid or invalid.
  4. Fix any reported issues and test again if needed.

Examples

Example

Input

services:
  web:
    image: nginx

Output

Valid YAML

A correctly indented YAML structure passes validation.

Example

Input

services:
	web:
  image: nginx

Output

Invalid YAML

Mixed tabs and broken indentation can cause validation errors.

Common errors

Tabs are used where spaces are expected.

Fix: Replace tabs with spaces and recheck the YAML.

Indentation levels are inconsistent.

Fix: Review the nesting carefully and keep indentation aligned.

The user expects formatting cleanup instead of syntax checking.

Fix: Use the YAML formatter if layout is the main problem rather than validity.

FAQ

What does YAML Validator check?

It checks common YAML problems such as tabs, inconsistent indentation, malformed list items, and simple quote issues.

Is this a full schema validator?

No. It focuses on practical syntax validation for common YAML mistakes in everyday config files.

When is this useful?

It is useful before saving, deploying, or committing YAML files that must parse correctly.

Is this YAML validator free to use?

Yes. It works online in the browser.

When should I use YAML Validator instead of YAML Formatter?

Use the validator when you want to catch syntax mistakes. Use the formatter when you mainly want cleaner spacing and layout.

Use cases

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