How to apply conditional formatting with a formula

Formulas allow you to make powerful and flexible conditional formatting rules that highlight just the data you want.

Let’s take a look.

The main requirement is that the formula return either TRUE or FALSE.

When a formula returns TRUE, the rule is triggered and the formatting is applied.

There is no preset for this, so we’ll need to use a formula.

The easiest way to test for odd numbers is to use a special function called ISODD.

ISODD takes just one argument, a number.

If I supply a reference to a cell that contains an odd number, the formula returns TRUE.

If the number is even, the formula returns FALSE.

This will work perfectly for conditional formatting.

As always, the formula must begin with an equal sign.

For the reference, look at the active cell in your selection.

This is the address you’ll want to use in the formula.

When we create the rule, Excel will adjust all references to be relative to the active cell.

In this case, we want to use B4.

For the format, I’ll use an orange fill and finish the rule.

As you’re able to see that all odd numbers are now highlighted.

If I change an odd number to an even number, we’ll see it highlighted as well.

when you obtain a formula, it’s possible for you to revise it as you like.

Now the formatting is applied to all even numbers.