Assume that you are having data in A column like the below:-
A1 cell
ABC
A2 cell
Abc
Paste this formula in B1 cell
=IF(EXACT(A1,UPPER(A1)),LOWER(A1),A1)
Now copy the B1 formula and paste it to B2 cell.
The result will be
B1 cell
abc
B2 cell
Abc
The above formula will convert the text to lower case only if the cell
consist the characters in Upper case. It will get the same result when the
text entry is in Proper OR Lower case.
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