If your macro is changing font name and font size, this isn't a big concern because conditional formatting won't affect these attributes. One thing to keep in mind with macros that affect formatting is that if you have conditional formatting applied to a cell that is also checked by a macro, the formatting in the conditional formatting takes precedence over the formatting in the macro. If they do, then the checking is done on the cells in the Target range. The macro uses the Union function to check whether the cells changed (passed to the event handler in the Target variable) have any overlap with the range you want checked. If Union(Target, Range("A1:A10")).Address = _ Private Sub Worksheet_Change(ByVal Target As Range) The following version is also added to the worksheet object: In that case, you may want to design the macro so it runs whenever the worksheet is changed, but only takes action if the change was done to a cell in your target range. Discover how Excel conditional formatting can turn boring spreadsheets into visually vibrant, dynamic storytellers that magically adapt to your datawithout tedious reformattingand make important data literally jump at you from the screen. It will go very quickly if you are checking A1:A10 (ten cells), but may go much slower if you are continually checking B2:N465 (over 6,000 cells). One drawback of this macro is that it can get sluggish if you have a very large range for it to check. To have the macro check a different range, just change the addresses assigned to the rng variable near the beginning of the macro. The result is that the formatting of the cells is checked and changed continuously. It checks the range A1:A10, applying the same tests as in the previous macro. This macro, when added to the worksheet object, will run every time the worksheet is recalculated. If you want the formatting to change more automatically, then you can have the macro check to see if a change was made within a certain range of cells: To use the macro, just select the cells you want changed and then run the macro. If any of the cells have a length of more than two characters or a value of more than 10, then the cell's font is changed. Consider the following macro, which examines any cells you have selected when you run the macro. You can, however, use a macro to examine cell contents and make changes in the appearance of a cell. (The controls that allow you to specify font name and size are grayed-out in the formatting dialog box used with conditional formatting.) The short answer is no, that can't be done-at least not with conditional formatting.
Robin asks if there is a way to use Excel's conditional formatting capabilities to change the font used in a cell or to change the font size in a cell.