How To Calculate Hours Between 2 or 3 Days Exclude Non Working Hours?

Which are the non working hours / days ?

working 7 days a week?

Try this formula

=(INT(E2)-INT(D2))*("22:00"-"8:00")+MEDIAN(MOD(E2,1),"8:00","22:00")-MEDIAN(MOD(D2,1),"8:00","22:00")

custom format result cell as [h]:mm

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