Compare
JSON vs YAML
JSON is a strict text format widely used for APIs and data exchange between programs. YAML offers syntax suited to human-edited configuration and structured data. Choose for the ecosystem and workflow.
Which format should you choose?
Use JSON for interoperable API payloads and program-to-program exchange. Consider YAML for configuration that benefits from comments and concise hierarchy, after validating it with the target parser.
Good fit for JSON
Web APIs, configuration files, and data exchange
- Transferring structured data
Good fit for YAML
Configuration files and structured-data authoring
- Settings maintained by people
Basic information
| Field | JSON | YAML |
|---|---|---|
| Extension | .json | .yaml, .yml |
| MIME type | application/json | application/yaml |
| Common uses | Web APIs, configuration files, and data exchange | Configuration files and structured-data authoring |
| How to open | Open it in a text editor, IDE, or JSON-aware viewer. | Open it in a text editor or YAML-aware tool and preserve space indentation. |
| Export or convert | Applications or conversion tools can convert it to formats such as CSV. | When the recipient requires JSON, convert it and check value types and character encoding. |
Choose by use case
Transferring structured data
Web APIs, configuration files, and data exchange
JSONSettings maintained by people
Configuration files and structured-data authoring
YAMLKey point 1
JSON uses explicit syntax for objects and arrays and is standardized for data interchange.
More on the differencesKey point 2
YAML supports comments and flexible human-readable representations often used in configuration files.
More on the differencesMore on the differences
Choose the format supported consistently by your tools and schema. Validate input, avoid ambiguous YAML constructs, and use safe parsing for untrusted data.
- JSON's stricter syntax can make generation and parsing predictable across environments.
- YAML can be easier for people to edit, but indentation and parser rules must be consistent.
- Both need schema validation when fields and types are important to an application.
- Do not treat YAML as a strict superset of JSON. Use the format required by the interface, and test parser behavior because YAML implementations can interpret some plain values differently.
Frequently asked questions
Is YAML always easier than JSON?
Not for every team or tool. YAML is often convenient for hand-edited configuration, while JSON is common for APIs and strict machine interchange.
Is YAML always better for configuration?
No. YAML can be readable for humans, but JSON may be better when a tool or interface expects JSON or consistent parsing is important.