JSON to YAML Converter

Convert JSON to YAML for Kubernetes, Docker Compose, and configuration files.

FreeNo signupRuns in browser
Input JSON
Output YAML
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When to use YAML over JSON

Configuration files

YAML is the standard for Kubernetes, Docker Compose, GitHub Actions, and most DevOps tooling. More readable than JSON for configs.

Comments support

Unlike JSON, YAML supports comments using #. Essential for documenting config values in large infrastructure files.

Less verbose

YAML uses indentation instead of brackets, resulting in files that are 20–40% shorter than equivalent JSON.

JSON to YAML — Converting API Data to Configuration Format

JSON and YAML represent the same data structures but serve different audiences. JSON is optimized for machines — compact, strict, fast to parse. YAML is optimized for humans — no braces, no quotes for simple values, support for comments. Converting JSON to YAML is most common when moving data from an API response into a configuration file, Kubernetes manifest, or Docker Compose file.

Why DevOps engineers convert JSON to YAML

Kubernetes and Docker Compose only accept YAML configuration. When you have JSON data from a tool or API and need to create a manifest, converting saves you from manually rewriting everything. GitHub Actions, Ansible, and Helm charts all use YAML — so if you're generating configs programmatically from JSON data, this conversion is essential.

Key differences in the output

YAML removes all braces, brackets, and most quotes. {"name":"nginx","replicas":3} becomes name: nginx replicas: 3. Arrays become dash-prefixed lists. Nested objects become indented blocks. The data is identical — only the syntax changes. YAML is typically 30–40% shorter than equivalent JSON for config files.

YAML indentation rules

YAML uses spaces for indentation — never tabs. The YAML spec forbids tab characters. Two spaces per indentation level is the de facto standard in the Kubernetes and Docker ecosystem. This converter always outputs properly space-indented YAML that passes validation in all major YAML parsers.

Frequently asked questions

How do I convert JSON to YAML online for free?
Paste your JSON into the input box and click Convert. The tool uses the js-yaml library running in your browser to instantly produce clean YAML output. No signup, no upload, completely free. Download the result as a .yaml file or copy it directly.
Is YAML a superset of JSON?
Yes. Any valid JSON is also valid YAML — the YAML spec is a superset. However, YAML adds many features that JSON doesn't have: comments with #, multi-line string literals, anchors and aliases for reusing values, and multiple documents in a single file.
What is the difference between JSON and YAML format?
JSON uses curly braces and square brackets to define structure and requires quoted strings. YAML uses whitespace indentation to define hierarchy and doesn't require quotes for most strings. JSON is preferred for APIs; YAML is the standard for configuration files like Kubernetes manifests and Docker Compose.
Can I convert JSON Kubernetes manifests to YAML?
Yes. Kubernetes supports both JSON and YAML, but YAML is the standard format used in practice. Paste your JSON Kubernetes manifest (Deployment, Service, ConfigMap, etc.) and click Convert to get the YAML equivalent, ready to apply with kubectl.
Why must YAML use spaces and not tabs?
The YAML specification explicitly forbids tab characters for indentation. Tabs will cause YAML parsing errors. Always use spaces — 2 spaces per level is the most common convention. This converter always outputs properly space-indented YAML.
Is my data safe when using this JSON to YAML converter?
Completely safe. The conversion runs entirely in your browser using the open-source js-yaml library. No data is sent to any server. You can verify this by disconnecting from the internet — the converter still works perfectly.