Last updated: March 2026
JSON vs YAML: Key Differences
JSON uses braces for objects, brackets for arrays, and requires quotes around all keys and string values. It's strict, unambiguous, and the lingua franca of web APIs.
YAML uses indentation instead of braces, supports comments, and is more human-readable. It's the standard for configuration files in DevOps tools like Kubernetes, Docker Compose, GitHub Actions, and Ansible.
When to Use YAML Over JSON
Use YAML for configuration files where humans will read and edit the file regularly. YAML's comment support and clean syntax make it ideal for deployment configs, CI/CD pipelines, and application settings.
Use JSON for data interchange where machines are the primary consumers. APIs, web storage, and data serialization benefit from JSON's strict parsing and universal library support.
Frequently Asked Questions
What is the difference between JSON and YAML?
JSON uses braces, brackets, and quotes. YAML uses indentation and colons. YAML is more human-readable and supports comments. JSON is more widely supported in APIs. Both represent the same data structures — objects, arrays, strings, numbers, booleans, and null.
Why convert JSON to YAML?
YAML is the standard for configuration files (Kubernetes, Docker Compose, GitHub Actions, Ansible, etc.). If you have JSON data or API responses that need to become config files, this converter saves manual conversion time.
Does YAML support comments?
Yes — YAML supports comments with # (hash). This is one of YAML's biggest advantages over JSON for configuration files. Comments let you document configuration options directly in the file.
Is the conversion lossless?
Yes. All JSON data types map directly to YAML equivalents. Strings, numbers, booleans, null, arrays, and objects all convert cleanly. The reverse (YAML to JSON) can lose comments since JSON doesn't support them.
What indent size should I use?
2 spaces is the most common YAML convention and is the default here. 4 spaces is also used, especially in Python-centric projects. Choose what matches your project's existing conventions.
Can I convert YAML back to JSON?
This tool currently converts JSON → YAML. For YAML → JSON, use our JSON Formatter tool which can parse YAML input. Or simply reverse the process: write your YAML, convert it here, and adjust as needed.