Where the hours-and-minutes calculator handles a single day, this one measures the full duration between two date-and-time combinations, however far apart they sit — from a few hours to several years — breaking the result down into a readable mix of days, hours and minutes rather than one large number.
It's suited to things like calculating exact project runtimes, the length of a stay somewhere, or the precise duration since an event with both a date and a time attached to it. Daylight saving changes falling inside the span aren't factored in automatically, so results spanning a DST transition should be checked against the local clock change.