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JSON YAML Converter

Convert between JSON and YAML formats

Conversion Mode:

Input

Output 

Converted output will appear here as you type...

Real-time Conversion

Instant conversion as you type with intelligent format detection and error handling.

File Upload Support

Upload JSON or YAML files directly for conversion with automatic format validation.

Export Options

One-click copy and download with proper MIME types and formatted output.

About JSON YAML Conversion

JSON YAML conversion transforms data between JSON (JavaScript Object Notation) and YAML (YAML Ain't Markup Language) formats. Both are popular data serialization standards used for configuration files, APIs, and data exchange between applications.

  • Bidirectional conversion between JSON and YAML
  • Preserves data structure and types
  • Handles nested objects, arrays, and complex data
  • Format validation and syntax error detection
  • Clean, readable output formatting

JSON vs YAML Format Comparison

JSON Features

  • Compact and machine-readable
  • Wide language support
  • Fast parsing performance
  • Standard for web APIs
  • Simple syntax with brackets and quotes

YAML Features

  • Human-readable and writable
  • Support for comments
  • Multi-line strings
  • Popular for configuration files
  • Indentation-based structure
Frequently Asked Questions

What is the difference between JSON and YAML?

JSON uses curly braces, square brackets, and mandatory double-quoted keys. YAML uses indentation for structure, supports comments with #, allows unquoted strings, and is more human-readable. JSON is better for APIs and machine parsing; YAML is preferred for configuration files (Kubernetes, Docker Compose, CI/CD). Both represent the same data structures.

Can I convert YAML back to JSON?

Yes, the utilAZ converter supports bidirectional conversion. You can convert YAML to JSON and JSON to YAML freely. However, YAML comments will be lost when converting to JSON since JSON has no comment syntax. All data values, arrays, objects, and nested structures are preserved accurately in both directions.

Why would I use YAML instead of JSON?

YAML is preferred when human readability matters, you need inline comments for documentation, you work with multi-line strings, or you use tools like Kubernetes, Ansible, Docker Compose, and GitHub Actions that use YAML natively. YAML also supports anchors and aliases for reusing data blocks, reducing duplication in large config files.

How do I convert JSON to YAML online?

To convert JSON to YAML online, paste your JSON into the utilAZ JSON YAML Converter and click convert. The tool instantly outputs properly indented, valid YAML. It handles nested objects, arrays, null values, booleans, and numbers. No sign-up required, and your data never leaves your browser.

How to handle comments in YAML to JSON conversion?

YAML supports comments using the # symbol, but JSON does not support comments at all. When converting YAML to JSON, all comments are stripped because they cannot be represented in JSON format. If you need to preserve documentation, consider storing comments as data fields (e.g., a "_comment" key) or keeping a separate YAML source of truth.

JSON vs. YAML at a Glance

The same data structure looks different in each format. JSON uses braces and quotes; YAML uses indentation and colons.

JSON

Curly braces {} for objects, square brackets [] for arrays, all keys and string values must be double-quoted.

Example: {"host": "localhost", "port": 5432}
YAML

Indentation for nesting, dashes for list items, no quotes required for most strings, supports comments with #.

Example: host: localhost / port: 5432

Paste either format into the converter above and get the other instantly.

Common Use Cases

  • Configuration file management
  • Docker and Kubernetes manifests
  • CI/CD pipeline configuration
  • API documentation (OpenAPI/Swagger)
  • Infrastructure as Code templates
  • Ansible playbooks
  • Data migration and transformation
  • Application settings conversion

YAML Syntax Essentials

Key YAML syntax rules to keep in mind when working with converted output:

Scalars and Mappings

key: value for strings, numbers, booleans, and null. Quotes are optional unless the value contains special characters like : or #.

Lists

Block style uses - item on each line. Flow style uses [a, b, c] inline. Both produce the same JSON array.

Multi-line Strings

Literal block | preserves newlines. Folded block > joins lines into one. Neither exists in JSON, so they become regular strings.

Comments

Lines starting with # are comments. These are lost during conversion to JSON since JSON has no comment syntax.

Converting in Code

After testing with our tool, you can automate JSON/YAML conversion in your projects using standard libraries.

Quick Reference by Language:

Python: yaml.dump(json.loads(s), default_flow_style=False)
JavaScript: yaml.dump(JSON.parse(jsonStr)) // js-yaml
Go: yaml.Marshal(data) // gopkg.in/yaml.v3
CLI (yq): yq -P '.' input.json > output.yaml

Our browser-based converter requires no installation and processes everything locally for privacy.