IconVault's YAML Formatter validates your YAML and rewrites it with clean, consistent formatting: normalized indentation, tidy lists and maps, and predictable quoting. If the YAML is invalid, you get a clear error message with the exact line and column where parsing failed, so fixing indentation errors or stray tabs takes seconds instead of guesswork.

One click switches the output to a pretty-printed JSON view, and you can copy or download either version. The YAML parser loads on demand to keep the page fast, and everything runs fully in your browser with nothing uploaded. It is free to try, with a limited number of free format runs before Pro is suggested.