Conversion happens entirely in your browser — nothing is uploaded.
What is a YAML Converter?
YAML and JSON describe the same kind of structured data with different syntax. YAML is friendlier for humans (Kubernetes, GitHub Actions, Docker Compose), JSON is friendlier for machines (APIs, configs, logs). DevTools Lab's YAML Converter performs lossless two-way conversion with strict validation, so you can quickly switch between the two formats while keeping types (numbers, booleans, dates) intact.
Features
- YAML → JSON conversion with type preservation
- JSON → YAML conversion with proper indentation
- Strict validation — exact line of any syntax error
- Handles multi-document YAML (--- separators)
- Preserves numeric types, booleans and null values
- 100% browser-based, no data sent to a server
How to use
- Pick a direction: YAML → JSON or JSON → YAML.
- Paste your source content into the input panel.
- The converted output appears instantly on the right.
- Copy or download the result.
Frequently Asked Questions
Is the conversion lossless?
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For standard data types (string, number, boolean, null, array, object) yes. YAML-only features such as anchors / aliases are resolved into their final values.
Does it support YAML 1.2?
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Yes. The parser follows YAML 1.2 — for example "yes" / "no" / "on" are kept as strings, not auto-coerced to booleans.
Can I convert Kubernetes manifests?
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Yes. Multi-document YAML separated by --- is supported and converted to a JSON array.
Is my YAML / JSON sent anywhere?
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No. All conversion happens locally in your browser.
Why does my YAML break?
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YAML is whitespace-sensitive. Mixing tabs and spaces, or inconsistent indentation, are the most common causes. The error message shows the exact line.
Related tools
Canonical: https://devformatlab.com/en/yaml-converter