About online YAML and JSON conversion
Switch between YAML configs and JSON for debugging, mocks, and API docs. Direction is detected from whether input starts with { or [.
Parsing runs locally in your browser—nothing is uploaded.
Online YAML ↔ JSON capabilities
Auto direction
YAML text becomes indented JSON; JSON objects or arrays become YAML with readable spacing.
What converts cleanly
- Maps, lists, strings, numbers, booleans, and null—typical config shapes.
- JSON is a subset of YAML syntax, so many YAML files round-trip through JSON.
- Anchors, aliases, and custom tags are not preserved—use plain YAML for this tool.
When to double-check
- Very large numbers: YAML may parse them as integers; JSON has fixed number rules.
- Multi-document files (--- separators): convert one document at a time.
Common use cases
Kubernetes & CI configs
Turn a deployment YAML fragment into JSON for jq, policy tests, or API payloads.
Local dev & mocks
Paste JSON from an API response and get YAML for docker-compose or Spring-style configs.
Docs & code review
Compare the same data in both formats when reviewing README or OpenAPI examples.
Frequently asked questions
- Is YAML a superset of JSON?
- Every JSON document is valid YAML, but YAML adds features (comments, anchors, unquoted strings). This tool focuses on data structures both formats share—maps, lists, and scalars.
- Why does my YAML fail to convert?
- Common causes are inconsistent indentation (YAML is whitespace-sensitive), tabs instead of spaces, or a stray character before the first key. Fix indentation or paste a smaller snippet to locate the error.
- How are booleans and null handled?
- YAML true/false/null become JSON true/false/null. Quoted "yes"/"no" stay strings in JSON, which matches how strict JSON parsers behave.
- Can I convert multiple YAML documents at once?
- No—paste one document per run. Split on --- lines and convert each block separately.