What This Tool Does
This converter transforms YAML configuration files into JSON and JSON back into YAML. Useful for Kubernetes manifests, GitHub Actions workflows, Docker Compose files, OpenAPI specs, and any configuration-as-code workflow where both formats are used interchangeably.
Inputs Explained
- Direction: YAML → JSON or JSON → YAML.
- Input: Paste YAML or JSON document.
- Indent: Output indentation level (2 or 4 spaces).
How It Works
YAML to JSON: parses a subset of YAML (keys, values, nested mappings, sequences, and common scalar types) into a JavaScript object, then serializes with JSON.stringify. JSON to YAML: walks the JSON tree and emits YAML syntax with proper indentation, quoting strings that contain special characters.
Formula / Logic Used
YAML to JSON & JSON to YAML Converter
Convert between YAML and JSON — perfect for Kubernetes, CI configs, and API specs.
Step-by-Step Example
Input YAML:
name: Ramesh age: 30 skills: - javascript - python
Output JSON:
{
"name": "Ramesh",
"age": 30,
"skills": ["javascript", "python"]
}
Use Cases
- Kubernetes manifests: Convert existing JSON configs to YAML for kubectl apply.
- GitHub Actions / CI: Transform JSON workflow data into YAML pipeline files.
- Docker Compose: Convert JSON configs to docker-compose.yml format.
- OpenAPI specs: Switch API documentation between YAML and JSON representations.
- Config file migration: Move application configuration between YAML-based and JSON-based tools.
Assumptions and Limitations
- The YAML parser supports a common subset (mappings, sequences, scalars, comments). Advanced features like anchors, aliases, and multi-line strings may not parse correctly.
- YAML allows multiple document separators (---) — only the first document is processed.
- Comments in YAML are stripped during conversion (JSON doesn't support comments).
- For mission-critical configs (especially Kubernetes), validate the output with the target tool before deploying.
Frequently Asked Questions
What is YAML?
YAML (YAML Ain't Markup Language) is a human-readable data serialization format. It's a superset of JSON and uses indentation instead of braces. Popular in DevOps for Kubernetes, Docker Compose, Ansible, and GitHub Actions.
Is every JSON valid YAML?
Yes. YAML 1.2 is a proper superset of JSON — any valid JSON document is also valid YAML. The converter produces idiomatic YAML (indentation-based) rather than JSON-in-YAML.
What YAML features aren't supported?
This lightweight parser handles common cases but may not support: anchors and aliases (&, *), custom tags (!!str, !!int), multi-line strings (|, >), and multi-document files (---). Use js-yaml for full spec compliance.
Why does my YAML convert differently than expected?
Common issues: inconsistent indentation (mix of tabs and spaces), unquoted values that look like booleans or numbers (true, 42, yes), and missing spaces after colons. The converter expects consistent 2-space or 4-space indentation.
Can I convert Kubernetes manifests?
Yes for most manifests. Simple Deployments, Services, and ConfigMaps convert cleanly. Complex CRDs with anchors or multi-document files (multiple --- separators) need manual splitting first.
Does the tool preserve key order?
Yes. JavaScript objects preserve insertion order in modern browsers, so the key order from input is maintained in output.
Are comments preserved?
No. JSON doesn't support comments, so YAML comments are stripped when converting to JSON. When converting JSON back to YAML, no comments are added.
Is my data uploaded?
No. Conversion runs entirely in your browser. YAML and JSON inputs never leave your device.
Sources and References
- YAML 1.2 Specification — Official YAML format specification.
- js-yaml Library — Full-featured YAML parser for JavaScript.
- ECMA-404 — JSON Standard — JSON format specification.
- Kubernetes — Configuration — Common YAML use case in Kubernetes.