Free YAML Formatter & Validator
Format YAML, validate syntax and convert YAML to readable JSON directly in your browser.
Format and Validate YAML
Paste YAML below to clean indentation, check syntax and generate formatted output.
What Can the YAML Formatter Do?
Clean and inspect YAML without manually fixing every indentation issue.
Format YAML
Convert inconsistent YAML into cleaner structured output with two-space or four-space indentation.
Validate Syntax
Parse YAML and identify syntax errors before using it in a configuration or deployment file.
Convert YAML to JSON
Convert structured YAML data into a readable JSON representation.
Normalize Indentation
Make nested objects and lists easier to inspect by applying consistent spacing.
Copy Clean Output
Copy formatted YAML or JSON directly into your editor or project.
Download the Result
Save formatted output as a YAML or JSON file for later use.
How to Format YAML Online
Clean YAML in a few simple steps.
What Is YAML?
YAML is a human-readable data serialization format commonly used for configuration and infrastructure files.
Application Configuration
YAML is frequently used to store settings for applications, frameworks and development tools.
CI/CD Pipelines
Many continuous integration and deployment platforms use YAML to define automated workflows.
Infrastructure
YAML can describe services, resources and configuration in infrastructure and container workflows.
Common YAML Formatting Problems
Small formatting mistakes can prevent YAML from parsing correctly.
Incorrect Indentation
Nested values depend on spacing, so inconsistent indentation can change structure or create syntax errors.
Tabs Instead of Spaces
YAML commonly expects spaces for indentation, making tabs a frequent source of formatting problems.
Broken Lists
Incorrectly positioned dashes or indentation can make list structures invalid.
Invalid Nesting
Parent and child values need consistent indentation to represent the intended hierarchy.
Quoting Issues
Certain values may need quotes depending on their contents and how they are intended to be interpreted.
Unexpected Syntax
A missing colon or malformed structure can prevent an otherwise simple YAML document from parsing.
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Developer Resources
Frequently Asked Questions
What is a YAML formatter?
A YAML formatter parses YAML data and outputs it with consistent indentation and structure so it is easier to read and maintain.
Does this tool validate YAML?
Yes. The formatter attempts to parse the YAML and reports an error when the syntax is invalid.
Can I convert YAML to JSON?
Yes. Select JSON as the output format before running the formatter.
What indentation should YAML use?
YAML typically uses spaces for indentation. Two spaces are common, although some teams prefer four spaces for readability.
Why is YAML indentation important?
Indentation represents hierarchy in YAML, so incorrect spacing can change the meaning of the data or cause parsing errors.
Can I download formatted YAML?
Yes. After formatting the content, you can save the result as a YAML or JSON file.
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