How To Add Numbers in Excel:
The SUM Function Explained

Written by co-founder Kasper Langmann, Microsoft Office Specialist.

Most people know that Excel is a spreadsheet application that allows for entry and storage of data.

Beyond that, most people know that Excel can calculate arithmetic operations as well.

One of the most fundamental skills you need to learn when using Excel is: how to add numbers using SUM!
Kasper Langmann, Co-founder of Spreadsheeto

In this tutorial, you learn 3 methods to add numbers in Excel:

  1. Adding numbers using a formula
  2. Adding numbers using the function ‘SUM’
  3. Using Excel’s ‘Autosum‘ to automatically add numbers

Let’s get into it 🙂

Note: All examples in this article are done in Microsoft Excel 2016 for Windows.

Get your FREE exercise file

Before you start:

Throughout this guide, you need a data set to practice.

I’ve included one for you (for free).

Download it right below!

Download the FREE Exercise File

Download exercise file
Download free exercise file

How to Add Numbers with a Formula

The basics of adding numbers in Excel doesn’t even need a special function.

That said, we will look at just how simple Excel does make it with functions.

But more on that later…

The main idea when doing any calculation in Excel is to begin by typing an equals sign (‘=’).

Kasper Langmann, Co-founder of Spreadsheeto

This is done in the cell where you want to perform the calculation.

So, let’s look at adding two numbers in a cell.

Adding two numbers in a cell

Note that we have simply typed in ‘=1 + 1’ into cell A1.

This is enough to perform the operation and return the sum.

We don’t have to limit the equation to just two terms. We can add more numbers to the equation if we like.

Kasper Langmann, Co-founder of Spreadsheeto
Adding more numbers to the equation

Now you know about the concept of how to add literal number values in a cell.

Let’s look at how easy it is to do the same with cell references.

All we must do is type the cell references or select the cells that contain the values we want to add together.

Kasper Langmann, Co-founder of Spreadsheeto
SUM and cell references

Notice in this example that we have used the cell references for ‘C6’ and ‘C7’, each of which contain the value ‘2’.

As we would expect, our equation in ‘A6’(‘=C6 + C7’), returns the value ‘4’.

If there were more cells containing values we wanted to add to the equation, we could do the same thing we did with literal values before.

Of course, at some point, adding any more values to the equation becomes inefficient.

But there’s good news! Excel offers a perfect solution that makes adding values far more efficient…the ‘SUM’ function.

Kasper Langmann, Co-founder of Spreadsheeto

How to Sum Numbers Using ‘SUM’

Instead of inputting the actual numbers (or cell references) and using the plus sign between them, simply type ‘=SUM’ to get started.

Then we add the numbers or cell references within parenthesis.

Let’s look at the syntax to get a better handle on what the formula should look like.

Kasper Langmann, Co-founder of Spreadsheeto

‘=SUM(number1, [number2], …)’

If you’re following along, just add the numbers you want to sum inside the parentheses (separated by commas) and it will look something like:

Adding two cells containing numbers using SUM

For literal number values, the benefit of the ‘SUM’ function is somewhat arguable.

Is it any more efficient to type in the numbers this way than it is to just type the numbers with plus signs in between?

Probably not, BUT…

The real value using ‘SUM’ is when adding values that exist in cells within your worksheets. As we turn to that idea, it is worth noting that there are two approaches to this.

Kasper Langmann, Co-founder of Spreadsheeto

The first approach is very straight forward and similar to what we did with literal numbers.

You can simply list cell references of the numbers you want the ‘SUM’ function to compute separated by commas.

Cell references in action

The second approach to using the ‘SUM’ function is not quite as obvious, but very useful.

This approach uncovers the power and efficiency of ‘SUM’ because it uses ranges rather than single cell references.

Kasper Langmann, Co-founder of Spreadsheeto

This is extremely helpful when your needs go beyond just a few cells.

One of the easiest ways to see how powerful the SUM function is to sum a column in Excel.

This is a very common way to use the ‘SUM’ function.

SUM function and ranges

Don’t limit yourself in this respect.

Be mindful that you can also sum ranges that go beyond the simple single column or row.

SUM in multiple columns

But sometimes you might be working with data sets that are hundreds if not, thousands of lines.

Using the ‘SUM’ function is definitely an appropriate way to deal with that.

But what if I told you there was an even more efficient way to sum a column in Excel?

Kasper Langmann, Co-founder of Spreadsheeto

Autosum in Excel

Autosum is pretty much what it sounds like it is.

Autosum takes the ‘SUM’ function and makes applying it to a column (or a row) super easy.

Autosum can be found in the ‘Editing’ group on the ‘Home’ tab.

Select the cell just below the range of cells you would like to sum.

Then click on ‘Autosum’.

Excel will automatically select the entire column of cells with number values.

Example of Autosum

Taking Autosum further: Here’s its shortcut

Instead of clicking on ‘Autosum’ in the ‘Home’ tab, you can use a keyboard shortcut to do the exact same thing.

With the cell, just below your column of values selected, press ‘Alt + =’ and Excel automatically places the ‘SUM’ formula for the entire column range in that cell.

Now just press ‘Enter’ and you are done!

Autosum shortcut

This is a great way to put ‘SUM’ to use with precision and speed.

It’s just one of many shortcuts that allow you to do something quickly without ever needing to take your hands away from the keyboard.

Now that you have learned the various methods of getting a sum of numbers in Excel, you should be able to choose the one that fits your needs best. So, get out there and start adding with the speed and efficiency of a pro!

Kasper Langmann, Co-founder of Spreadsheeto