Conditionally formatting cells if their value equals any value of another column

Question

I have data in the A and B columns. B column\'s data is mostly duplicates of A\'s data, but not always. For example:

Answer 1

All you need to do for that is a simple loop.
This doesn't handle testing for lower case, upper-case mismatch. If this isn't exactly what you are looking for, comment, and I can revise.

If you are planning to learn VBA. This is a great start.

TESTED:

Sub MatchAndColor()

Dim lastRow As Long
Dim sheetName As String

    sheetName = "Sheet1"            'Insert your sheet name here
    lastRow = Sheets(sheetName).Range("A" & Rows.Count).End(xlUp).Row

    For lRow = 2 To lastRow         'Loop through all rows

        If Sheets(sheetName).Cells(lRow, "A") = Sheets(sheetName).Cells(lRow, "B") Then
            Sheets(sheetName).Cells(lRow, "A").Interior.ColorIndex = 3  'Set Color to RED
        End If

    Next lRow

End Sub