Comparisons
Data format comparisons
Picking the right format is an architecture decision. These side-by-sides cover syntax, speed, tooling, and real-world fit so you can choose with confidence.
JSON vs YAML
Use JSON for APIs and machine-to-machine data. Use YAML for human-edited config files (Kubernetes, CI, Ansible). Never use YAML where speed and strictness matter — the parser is 3–10× slower than JSON and accepts ambiguous inputs.
JSON vs XML
Default to JSON. Choose XML only when you need strict schema validation (XSD), mixed content (documents with markup), or interop with industries that haven't migrated (banking ISO 20022, healthcare HL7, legal filings, SOAP).
YAML vs XML
For modern DevOps, developer-facing config, and pipelines, use YAML. For document-oriented data, regulated industries, or anywhere strict schema validation is a contract, XML is still the better pick.
JSON vs CSV
Use CSV for tabular data that non-developers consume in Excel or Google Sheets. Use JSON for APIs, nested data, or anywhere types matter. For analytics pipelines, Parquet or Arrow beats both — but CSV and JSON remain the lowest-common-denominator formats.
YAML vs JSON
For config files humans edit: YAML (with a linter in CI). For config files generated by a program or consumed by browsers / APIs: JSON. Consider TOML if you want strict types without YAML's indentation traps.