# bool ```js // usages chance.bool() chance.bool({ likelihood: 30 }) ``` Return a random boolean value (`true` or `false`). ```js chance.bool(); => true ``` The default likelihood of success (returning `true`) is 50%. Can optionally specify the likelihood in percent: ```js chance.bool({likelihood: 30}); => false ``` In this case only a 30% likelihood of `true`, and a 70% likelihood of `false`.