UNIQUE

UNIQUE(array [,by_col] [,occurs_once])

Returns the array of unique values in a list, table or cell range.

array	The range or array from which to return unique values.
by_col	(Optional) A logical value indicating whether to compare rows or columns: True = Your data is arranged from left to right so you are comparing columns False = Your data is arranged from top to bottom so you are comparing rows (default)
occurs_once	(Optional) Whether to return values that occurs once: True = Return only unique values that occur once False = Return all unique values (default)

REMARKS

* Added in Excel 2021.
* This function can create a Dynamic Array Formula.
* If "by_col" is left blank, then False is used.
* If "by_col" = 1, then True is used.
* If "by_col" = 0, then False is used.
* If "by_col" = False and the data is arranged in a column, then unique items will be returned.
* If "by_col" = True and the data is arranged in a row, then unique items will be returned.
* If "by_col" = True and the data is arranged in a column (instead of a row), then every item is returned. Examples 4 & 9.
* If "occurs_once" is left blank, then False is used.
* If "occurs_once" = 1, then True is used.
* If "occurs_once" = 0, then False is used.
* If "occurs_once" = False, then all the unique values will be returned.
* If "occurs_once" = True, then only the unique values that occur once will be returned.
* If "occurs_once" = True and no values occur only once, then #CALC! is returned.
* If there are not enough blank cells to display the full array, then #SPILL! is returned. Example 10.
* You can use the SORT function to return an array of data that has been sorted.
* For the Microsoft documentation refer to support.microsoft.com

	A	B	C	D	E	F	G
1	=UNIQUE(B1:B4) = { Mon, Tue, Wed }	Mon	Tue	Tue	Wed		30
2	=UNIQUE(B1:B4,FALSE) = { Mon, Tue, Wed }	Tue		Tue			20
3	=UNIQUE(B1:B4,FALSE,FALSE) = { Mon, Tue, Wed }	Tue		Mon			10
4	=UNIQUE(B1:B4,FALSE,TRUE) = { Mon, Wed }	Wed		Mon			20
5	=UNIQUE(B1:B4,TRUE) = { Mon, Tue, Tue, Wed }
6	=UNIQUE(B1:B4,TRUE,TRUE) = { Mon, Tue, Tue, Wed }
7	=UNIQUE(B1:E1,TRUE) = { Mon, Tue }
8	=UNIQUE(G1:G4,FALSE) = { 30, 20, 10 }
9	=UNIQUE(G1:G4,TRUE) = { 30, 20, 10, 20 }
10	=UNIQUE(B1:B4) = #SPILL!
11	=UNIQUE(D1:D4,,TRUE) = #CALC!

1 - What are the unique values in the vertical range "B1:B4".
2 - What are the unique values in the vertical range "B1:B4".
3 - What are the unique values in the vertical range "B1:B4".
4 - What are the unique values in the vertical range "B1:B4" when the "occurs_once" argument is True.
5 - What are the unique values in the vertical range "B1:B4" when the "by_col" argument is True.
6 - What are the unique values in the vertical range "B1:B4" when the "by_col" argument is True and the "occurs_once" argument is True.
7 - What are the unique values in the horizontal range "B1:E1".
8 - What are the unique values in the vertical range "G1:G4".
9 - What are the unique values in the vertical range "C1:C4".
10 - What are the unique values in the vertical range "B1:B4". There are not enough blank cells to display the full array.
11 - What are the unique values in the vertical range "D1:D4" when the "occurs_once" argument is True. There are no items occurring only once.