I would like to convert between the Hijri calendar date and the Gregorian calendar date in Excel

officenizar 

Let's say you have Hijri dates in B2 and down.

To display them as Gregorian dates in the cells themselves, apply the custom number format B1dd/mm/yyyy to B2:B50.

Or to display the Gregorian format in C2:C50, enter the following formula in C2:

=B2

Apply the custom number format B1dd/mm/yyyy to C2, then fill down to C50.