Sum is probably one of the first functions most people learn in Excel. Sum is just a fancy word for add up.
What the sum function allows you to do is avoid a formula such as =A1+A2+A3+A4+A5+A6+A7.
The sum function takes a start cell, and an end cell and adds up all the cells in between. The fancy spreadsheet name for this is a range. In most spreadsheets, you show a range by putting the first cell, then a colon (:), and then the last cell. So =SUM(A1:A7) would replace the formula above. Notice too, that you have to put the range in brackets.
You can also put more than one range into the sum function. Separate each range with a comma.
=SUM(A1:A7, C1:C7) will add up all the numbers in A1 to A7 and C1 to C7.
Always remember to put an equal sign at the start of your formulas and functions.
The next step up from SUM, is SUMIF. This function allows us to choose which of a set of numbers we add together based on some criteria. The criteria might be something about the numbers themselves, or it might be a criteria that is related to those numbers in some way. An example will help.
Here we have summed all the numbers in C2 to C13 that are less than 100. Note that the criteria needs to be in quote marks.
The inputs for SUMIF are a little more complex and SUM.
=SUMIF(range, criteria, [sum_range]) Again, we can see we need to input a range. Then we also need to put in our criteria. Then an optional input is the sum range. We can tell it is optional by the [square brackets] around the sum_range. In the example above the range is giving us both the numbers to add up, and the criteria, so we don’t need the optional input.
In this example, we have entered that third optional input.
This formula is summing up the numbers in C2 to C13, when the value in B2 to B13 is Bowler. It will match up across the rows to decide which numbers to add.
If you have multiple criteria that you want to use, then you can use a SUMIFS formula.