convertTo :: String -> Date -> Number

Returns the time since the Unix epoch, in the specified unit (milliseconds, seconds, minutes, hours, days), of the supplied Javascript date object. Returns NaN if the unit of time or Javascript date object is not valid.

const date = new Date.UTC('2015-10-16T00:00:00+00:00')
D.convertTo('milliseconds', date) // 1444953600000
D.convertTo('seconds', date) // 1444953600
D.convertTo('minutes', date) // 24082560
D.convertTo('hours', date) // 401376
D.convertTo('days', date) // 16724