Regex to match a string with 2 capital letters only
Try =
^[A-Z][A-Z]$
Just added start and end points for the string.
You need to add word boundaries,
\b[A-Z]{2}\b
DEMO
Explanation:
\b
Matches between a word character and a non-word character.[A-Z]{2}
Matches exactly two capital letters.\b
Matches between a word character and a non-word character.
You could use anchors:
^[A-Z]{2}$
^
matches the beginning of the string, while $
matches its end.
Note in your attempts, you used [A-Z]{2, 2}
which should actually be [A-Z]{2,2}
(without space) to mean the same thing as the others.
You could try:
\b[A-Z]{2}\b
\b matches a word boundary.