Choose whether your input is decimal hours (e.g. 1.25 for one hour fifteen minutes) or total minutes (e.g. 135). The converter splits into hours and minutes with rounding appropriate to the mode. It does not handle seconds or negative durations.
Decimal hours: whole hours = floor(value), minutes = round((value − hours)×60) mod 60. Total minutes: the input is rounded to an integer minute count first, then split into hours and minutes. Negative values are rejected.
This calculator uses plain decimal numbers. If a result looks wrong, check whether you used a comma instead of a dot (or vice versa) where the field expects one.