Duplicate text find

[Manolocs]

Hello,
I concatenate two columns, and delete all spaces from the results, after that I conditional format to find duplicated texts. It works ok. My question is: Is there a way to check duplicate for the 10 first characters, or maybe 5 first ones?
it would help to find some differences in text.
Thanks in advance...

 

[Peter_SSs]

This is testing for the same first 3 characters, just change the 3 in the formula to whatever you want.

Excel Workbook
	B
1
2	abcdef
3	abcryu
4	plxt
5	plot
6	abfcd
7	plowing
8	abcwqt
9
CF same left

Cells with Conditional Formatting
Cell	Condition		Cell Format	Stop If True
B2	1. / Formula is =COUNTIF(B$2:B$8,LEFT(B2,3)&"*")>1	Abc

 

[Manolocs]

@Peter_SSs the formula gives only FALSE or TRUE. Am I doing something wrong?

 

[Peter_SSs]

@Peter_SSs the formula gives only FALSE or TRUE. Am I doing something wrong?

It is supposed to just give True/False but it should be used in Conditional Formatting, not a cell.
For my example, select B2:B8 then Home ribbon tab -> Conditional Formatting -> New Rule ... -> Use a formula to determine which cells to format -> Format values where this formula is true: =COUNTIF(B$2:B$8,LEFT(B2,3)&"*")>1 -> Format... -> Choose your format -> OK -> OK