How to convert YAML to JSON
Paste YAML on the left and the JSON appears on the right as you type. Switch to JSON → YAML to go the other way. If something is wrong, the message names the line so you can fix it quickly. Press Use output as input to check that a file survives the round trip.
What YAML is supported?
Everything you find in everyday config files: nested maps and lists, inline [lists] and {maps}, quoted and plain strings, comments, multi-line | and > blocks, anchors (&base), aliases (*base) and merge keys (<<: *base). That covers Docker Compose, Kubernetes manifests, GitHub Actions workflows and OpenAPI specs. Files with several documents separated by --- should be converted one document at a time.
Why is “yes” in quotes in my YAML?
Older YAML readers treat unquoted yes, no, on and off as true or false. When converting JSON to YAML, text values like these are quoted so every tool reads them as text, exactly as they were in your JSON. Numbers stored as text, like "42", are quoted for the same reason.
Common YAML errors
- Tabs — YAML only allows spaces for indentation.
- Bad indentation — every item of a map or list must line up exactly.
- Duplicate keys — the same key twice in one map is an error, not an override.