You can conditionally highlight cells containing formulas in Excel by using the Conditional Formatting feature. To do this, first select the cells you want to format. Then, on the Home tab, in the Styles group, click Conditional Formatting. Next, click Highlight Cell Rules, and then click Contains Formulas. Finally, click OK. The selected cells will now be highlighted.

Note: This technique will only work if the formulas are actually entered into the cells. It will not work if the formulas are entered as values.