How do I sum highlighted cells?

You cannot use color as a condition for a SUMIF. If there is some method behind the colors (such as "all values above 0 are green and all below 0 are red"), you can create a SUMIF using the same methodology. But if you are selectively coloring in cells and there is no pattern to it, you won't be able to create a SUMIF.

Assuming you are manually changing the background color of selected cells, maybe there is another way to get the cells colored in than that. Maybe you could use checkboxes or something that can be picked up by a formula. Without knowing or seeing what you are doing it is hard to tell from here.

SUMIF can compare content of cells with a fixed value or with the content of another cell to determine whether to include the value in an associated cell in a sum. It cannot detect or compare the format attributes of the cell or of it's content.

You may be able to use the condition controlling the format (fill colour) of these cells to control the content of another cell, then compare the content of that other cell to provide the SUMIF condition.

Further specifics would make a more detailed response possible.

Regards,

Barry

Format > Cell > Conditional Highlighting > Add a Rule > Choose a Tab for the data type in your comparison > Choose a Comparison Operator > Enter value or click on the cell icon and specify the cell containing the comparison value.

Use the same criteria and values in your SUMIF

Jerry