YAML Validator & Converter

How this reads your output

The direction is detected from what you paste, so JSON becomes YAML and YAML becomes JSON without choosing a mode. The interesting work happens on the way to YAML: any string that could be mistaken for another type gets quoted. That includes yes, no, on, off, anything resembling a number, and version strings, all of which YAML would otherwise convert to something else entirely.

What the results mean

Ambiguous strings quoted

Values that would be read as booleans or numbers if left bare. The count is worth glancing at, since each one would have been a silent type change.

Nesting depth

How deep the structure goes. YAML indentation errors get harder to spot with depth, which is why deeply nested configuration is worth restructuring.

Keys

Total keys across the whole structure, which is a rough measure of how much configuration you are dealing with.

Common problems and fixes

A value like "no" or "off" became false

This is the Norway problem, named after country lists that lose Norway because its code NO is read as the boolean false. Quote the value, which this converter does automatically in that direction. YAML 1.2 narrowed the rule to just true and false, but many parsers still implement the older behaviour.

A version number lost its trailing zero

It was read as a number, so 1.10 became 1.1. Version strings, postcodes with leading zeros and telephone numbers all need quoting for the same reason. Anything that looks numeric but is really an identifier should be a quoted string.

Frequently asked questions

More in DevTools

• JSON Tree ViewerExplore JSON as a collapsible tree, with the path of every value.
• XML to JSONConvert XML into JSON, with the mapping choices explained.