Conditional formatting for duplication - Two columns are involved

Highlight A2:H40 > Conditional Formatting > New Rule > Use a formula

=COUNTIFS($A:$A,$A2,$G:$G,$G2)>1

Format: Fill color of your choice > OK > OK

Thank you for the instant reply, 63falcondude. The formula worked!

You're welcome. Thanks for the rep!

One more question: Any tips for applying this to larger spreadsheets? Excel freezes when the formula is applied to the original sheet of 127,000 rows.

Thank you,

Try reducing the size of the referenced range in the formula.

That is, highlight A2:H127000 and use this formula:

=COUNTIFS($A$2:$A$127000,$A2,$G$2:$G$127000,$G2)>1

That being said, why do you want to apply Conditional Formatting to over 100,000 rows of data? Surely you aren't manually checking all of these rows.

If you want to remove the duplicated values, there are better/easier ways of achieving this.

Your guess is right. I'm trying to highlight all instances of duplication, but not necessarily remove them.

Still 'Not Responding' - but I'm not sure if the limiting factor is my hardware or the demands of the formula. Narrowing the data down to each month would net 12 sheets of ~10,580 rows. Maybe that will help.

Ideas for a better way would be greatly appreciated.

You sent me a PM asking for a better way to conditionally format your data.

A few things:

1) Please keep all communications within the public forums and not through private messages.
2) I said that there are better/easier ways to remove duplicate values.
3) If I knew a "better" way of Conditionally Formatting your data, I would have suggested that.