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Overview

YAML Formatter & Validator

Strictly format, validate, and beautify your YAML configurations. Instantly detect syntax errors with line-level precision. Essential for Docker and Kubernetes.

What isHow to useExampleCommon use casesFrequently asked questions

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Problems

5

FAQ

3

Quick links

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#format-docker-compose#fix-yaml-indentation#k8s-yaml-validator#strict-yaml-parser#check-yaml-syntax

YAML Formatter

Standard js-yaml Parser

What you can solve

How to check if yaml is valid online?

The most common YAML errors include mixing tabs and spaces for indentation, forgetting spaces after colons, or unescaped special characters in strings. The validator will point you to the exact character causing the issue.

Format kubernetes yaml file?

YAML (YAML Ain't Markup Language) is the standard for configuration files, widely used in Docker, Kubernetes, and CI/CD pipelines.

Convert json to yaml online?

Converting standard JSON API responses into readable YAML formats. Can I convert JSON to YAML with this? Yes. Since JSON is technically a valid subset of YAML, pasting JSON into the input will format it cleanly into YAML. Everything runs locally in the browser, which keeps the workflow fast and privacy-friendly.

Fix yaml indentation error?

The most common YAML errors include mixing tabs and spaces for indentation, forgetting spaces after colons, or unescaped special characters in strings. The validator will point you to the exact character causing the issue. However, its strict reliance on indentation makes it prone to syntax errors. YAML (YAML Ain't.

Online yaml syntax checker tool?

This tool uses the industry-standard `js-yaml` engine to parse, validate, and reformat your code instantly.

Typical workflow

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Guides for this workflow

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What is

What is YAML Formatter & Validator?

YAML (YAML Ain't Markup Language) is the standard for configuration files, widely used in Docker, Kubernetes, and CI/CD pipelines. However, its strict reliance on indentation makes it prone to syntax errors. This tool uses the industry-standard `js-yaml` engine to parse, validate, and reformat your code instantly.

How to use

How to use YAML Formatter & Validator

Paste your raw YAML or JSON into the input area. Choose your preferred indentation (2 or 4 spaces) and whether to sort keys alphabetically. Click 'Format & Validate'. If there is a syntax error, the tool will highlight the exact line and column where the parsing failed.

Example

Example

Input:
server:
  port: 8080
environment:   production

Output (2 Spaces):
server:
  port: 8080
environment: production

Common use cases

Common use cases

1. Validating Kubernetes deployment files (.yaml) before applying them to a cluster.

2. Beautifying messy or minified Docker Compose configurations.

3. Converting standard JSON API responses into readable YAML formats.

4. Alphabetizing massive configuration files for easier manual reading.

Frequently asked questions

Frequently asked questions

Is my YAML configuration secure?v
Absolutely. Your data is parsed and formatted entirely within your browser's memory using a local JavaScript engine. We do not track or store your input.
Can I convert JSON to YAML with this?v
Yes. Since JSON is technically a valid subset of YAML, pasting JSON into the input will format it cleanly into YAML.
Why does my YAML fail validation?v
The most common YAML errors include mixing tabs and spaces for indentation, forgetting spaces after colons, or unescaped special characters in strings. The validator will point you to the exact character causing the issue.