YAML Toolkit
Validate and format YAML — syntax errors, duplicate keys, parser-version gotchas, and consistent indentation — schema-agnostic, for any YAML file. All run entirely in your browser.
How these fit together
YAML Validator checks that a YAML file is well-formed — syntax errors, duplicate keys, tab indentation, unresolved aliases — plus a note on the classic yes/no/NO boolean ambiguity between YAML 1.1 and 1.2 parsers. It's schema-agnostic, checking the YAML itself rather than what any particular application expects it to contain — for Kubernetes-specific validation against real API rules, see the Kubernetes Toolkit instead. Once a file is valid, YAML Formatter re-indents it to a consistent width, with comments preserved and key order left untouched — safe to run on a file you haven't fully reviewed yet, since it reports the same parse errors instead of formatting broken YAML into something that merely looks plausible.