Duplicates in multiple columns

[Yamasaki450]

Hello everyone... I need some help again.

I would like to find duplicates in multiple columns. What would be the easiest way to do this?
I tried to select all columns and search duplicates with conditional formatting but Excel just locks up or not responding...
I guess there is too much data 750 000 rows.

How would you do this? Any advice? Thanks.

It looks like this.

 

[etaf]

what version of Excel - I'm using latest 365 version
what type of PC/Laptop - I'm using an Apple M1 Macbook pro with 16GB memory

I tried and found a few duplicates with 750,000 rows from column A to AA and was instant - although i have not populated a lot of data and that maybe the issue

i selected the entire workbook - using the box between the Column Letters and row numbers

I used a formula

=AND(A1<>"",COUNTIF($A$1:$AA$750000,A1)>1)

I also have data in rows 745,000 to 750,000 - not shown here

ConD-Frmt-Icons-ETAF.xlsx
	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O
1
2
3			2	3	4	5	6	7	8	9	10	11	12	13
4			12				14
5							14
6							14
7					1		14
8							14
9							14		1
10							14
11							14
12							14
13							14
14							14
15							14
16
17
18
19
20
21
22
23
Sheet2

Cells with Conditional Formatting
Cell	Condition		Cell Format	Stop If True
1:1048576	Expression	=AND(A1<>"",COUNTIF($A$1:$AA$750000,A1)>1)	text	NO

 

[Yamasaki450]

Thanks. But this formula not working for me... Im using Excel 2019 but formula should still work right?

 

[Fluff]

Im using Excel 2019

I suggest that you update your Account details (or click your user name at the top right of the forum) so helpers always know what Excel version(s) & platform(s) you are using as the best solution often varies by version. (Don’t forget to scroll down & ‘Save’)

 

[etaf]

you are putting the formula in A1 - its a conditional formatting rule - or put in another column
its using A1 as a reference , which may be the issue


Note: Images are difficult to see , and also requires that I input all the data myself, which is very time consuming.

A SMALL sample spreadsheet, around 10-20 rows, would help a lot here, with all sensitive data removed, and expected results mocked up and manually entered, with a few notes of explanation.

MrExcel has a tool called “XL2BB” that lets you post samples of your data and will allow us to copy/paste your sample data into our Excel spreadsheets, saving a lot of time.

XL2BB - Excel Range to BBCode

Excel 'mini-sheet' in messages - XL2BB Although experts prefer to read your description and question instead of working in your actual file to solve your problem, there are times that it is difficult to explain an issue without providing actual...

www.mrexcel.com

You can also test to see if it works ok, in the "Test Here" forum.

Test Here

Use this forum to test your signature, learn bbcode, smilies, XL2BB, etc. Threads in this forum are automatically deleted after no replies for seven (7) days

www.mrexcel.com

OR if you cannot get XL2BB to work, or have restrictions on your PC , then put the sample spreadsheet onto a share
I only tend to goto OneDrive, Dropbox or google docs , as I'm never certain of other random share sites and possible virus.
Please make sure you have a representative data sample and also that the data has been desensitised, remember this site is open to anyone with internet access to see - so any sensitive / personal data should be removed

 

[etaf]

for 2007, 2010 , 2013 , 2016 , 2019 or 365 Subscription excel version
Conditional Formatting

Highlight applicable range >>
A1:AA750000 - Change, reduce or extend the rows to meet your data range of rows

Home Tab >> Styles >> Conditional Formatting
New Rule >> Use a formula to determine which cells to format
Edit the Rule Description: Format values where this formula is true:
=AND(A1<>"",COUNTIF($A$1:$AA$750000,A1)>1)

Format [Number, Font, Border, Fill]
choose the format you would like to apply when the condition is true
OK >> OK

 

[Yamasaki450]

Got it working. I had to replace commas with semicolons in formula. So the formula looks like this =AND(A1<>"";COUNTIF($A$1:$AA$750000;A1)>1) and it works.
The problem is excel becomes very laggy after applying formula... It finds duplicates buts scrolling up and down becomes laggy after that.
I will try to update office to the newest version maybe this will help if not the problem is in my PC. Im still using older quad core Intel Q9550 and 8GB DDR2 heh

Thanks a lot for your help etaf.

 

[etaf]

you are welcome, maybe PC - also referring to 750000 rows - VBA may be more efficient, but i dont provide solutions for VBA here