Dim d As Date
  Dim m1, m2, min As Long
 
  m1 = DateDiff("n", d, TimeValue("21:30"))
  m2 = DateDiff("n", d, TimeValue("05:45"))
  min = m1 + m2 ' Gesamt Minuten = 1635
 
  ' Umrechnung:
  Dim std As Double
  std = min / 60 ' Gesamt Stunden = 27,25
  ' oder
  Dim Stunden, Minuten As Integer
  Stunden = min \ 60 ' 27 Stunden und
  Minuten = min Mod 60 ' 15 Minuten