YAML

YAML Cheat Sheet

Indentation, types, and common YAML pitfalls. Format and validate YAML online with FreeToolMate — files stay on your device.

Basic document

name: Ada
active: true
score: 42
tags:
  - yaml
  - config
profile: null

Rules that trip people up

• Indentation matters — use spaces, not tabs
• Maps use key: value; lists use - items
• Strings with : or leading * often need quotes
• true / false / null / numbers are typed unless quoted
• Comments start with #

Nested map

server:
  host: localhost
  port: 8080
  tls:
    enabled: false

FreeToolMate YAML tools

• YAML Formatter — beautify config files
• YAML Validator — catch indentation and syntax errors
• JSON Beautify when you convert to or from JSON

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