Let excel do math for you regardless of whatever condition you are in. From planning the monthly budget of a common man to balance sheet of an organization, Autosum in excel is a one-click tool in Microsoft Excel that runs functions on a list of data. A handy yet powerful function in Microsoft Excel that can automatically add up a range of cells quickly by saving your time. It’s often faster than creating a formula when you have large sets of data to add up.
I prepared a list of data that I want to add up and let us see, how to do that.

1. In the below scenario, we need to know how much sales we have done at the end of the year for individual location and let’s look how we shall use this AutoSum function.
2. Instead of typing the sum formula, on the right hand side of the home tab, you will be able to find the option AutoSum. Now, click on the dropdown and you shall find several options such as sum, average, count, max, and mind. As we are looking up for the total, select the sum option
3. When you chose the option of Autosum from the ribbon, it automatically guess the range of cells to be added. You can even change the range, it is mutable.
4. Hit enter and you shall receive the sum of the entire column you have selected. There you go.

Likewise, you can perform other operations by selecting the respective option in the AutoSum dropdown.

Things to remember while using AutsoSum function in Excel:

● Autosum can only go up or left, not right or down.
● You can also press ALT+= (on Windows) or Option+Command+= (on Mac) as an alternative to clicking the Autosum button on the toolbar.
● Autosum stops when it encounter an empty cell or a cell that doesn't contain a number.
● Autosum stops functioning when it hits any non-numeric value in your range. Strictly speaking, the Autosum formula will work but the error will stop it calculating the result

https://www.edupristine.com/blog/auto-sum-function-in-excel