Tools // Automation

YAML Validator

Validate//Convert YAML ↔ JSON

About this validator

A dependency-free YAML parser covering the common subset: block mappings & sequences, plain and quoted scalars, comments, flow [ ] / { }, and block scalars | / >. It follows YAML 1.2-style core types, so it stays out of the classic footguns:

Duplicate mapping keys are flagged as errors.
Leading-zero numbers (007) and colon values (12:30) are kept as strings, not octal/base-60.
When converting JSON→YAML, ambiguous strings (e.g. 007, yes, on) are auto-quoted so the output is safe for any parser.
Not supported: anchors/aliases, tags, and multi-document streams (---).

01 // Validate

YAML → JSON

Validate YAML and convert it to JSON.

YAML Input

02 // Convert

JSON → YAML

Paste JSON to convert it to YAML. For deep JSON debugging, use the JSON Syntax Tester.

JSON Input

YAML's friendly traps

YAML is a superset of JSON that trades braces for indentation — which is exactly where it bites. A few rules save most of the pain:

Spaces only, never tabs — a single tab character breaks the whole document.
Indentation is structure — misaligning by one space silently changes the nesting, and therefore the meaning.
Implicit types — bare yes/no/on/off become booleans, 3.20 becomes the number 3.2 (dropping the zero), and a leading-zero value can be read as octal. Quote strings when in doubt.
Anchors & aliases — &name defines a reusable block and *name repeats it; powerful, but easy to misread.

This tool validates with clear line/column errors and converts both ways between YAML and JSON, so you can round-trip an Ansible playbook or a Kubernetes manifest and confirm it parses the way you intended.

JSON Syntax Tester · Config Template Generator
Shell & cloud CLIs — where these files get applied.

YAML → JSON

JSON → YAML

YAML's friendly traps

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