How to Sum in Excel: AutoSum, Shortcut and Formula

Adding up a column is usually the first thing anyone does in Excel, whether it's hours worked for a client, orders in a week or followers gained across platforms. There are three ways to do it, and the fastest takes one click.

I'll also show you why typing a long chain of plus signs is a habit worth breaking. Microsoft's own help explains the errors it causes, and once you've seen them you'll use SUM for everything.

Summing a column in Excel with AutoSum

This is the one-click route, and it works the same way in Excel for Windows, Excel for Mac and Excel for the web. Microsoft's steps:

1. Click the empty cell directly below the last number in your column.
2. On the Home tab, select AutoSum. You'll also find it on the Formulas tab.
3. Excel highlights the cells it plans to add. Check the highlight covers the right numbers.
4. Press Enter.

Excel writes a SUM formula for you, and the total appears in the cell. Click it and you'll see the formula in the bar at the top, such as =SUM(A2:A10). Because it's a live formula, the total updates by itself whenever you change one of the numbers above it, so you never need to redo the sum when a client adds an extra hour or an order gets cancelled.

To total a row instead, click the empty cell directly to the right of the last number in the row, then do the same.

Adding up several Excel columns at once

Here's a time-saver Microsoft points out. If you've got columns side by side, select all the empty cells under them, for example B7 and C7, then select AutoSum. Excel totals both columns in one go.

You can also total one column and copy the formula across. Microsoft's example: copy B7 to C7 and the formula automatically adjusts to add C3 to C6 instead. That's because Excel shifts the cell references when you copy a formula.

The keyboard shortcut for SUM in Excel

On Windows, click your empty cell and press Alt and the equals sign together. Excel adds the SUM function, guesses the range, and you press Enter to accept it. I use this all the time for quick totals in a tracker.

Typing a SUM formula yourself in Excel

Sometimes AutoSum guesses the wrong cells, or you want to add numbers that aren't next to each other. Then type it.

1. Click the cell where you want the total.
2. Type =SUM( and then select the cells you want to add with your mouse.
3. To add a second block, type a comma and select it too.
4. Close the bracket and press Enter.

Microsoft's examples show the pattern: =SUM(A2:A10) adds one range, and =SUM(A2:A10, C2:C10) adds two. The colon means everything from the first cell to the last. Microsoft says you can include up to 255 numbers or ranges in one SUM.

Why SUM beats plus signs in Excel

It's tempting to write =A1+B1+C1. It works, until it doesn't. Microsoft lists the problems:

Problem	Plus-sign formula	SUM formula
A cell contains text	Shows a #VALUE! error	Ignores the text and adds the numbers
You delete a row	Can break with #REF!	Adjusts automatically
You insert a row inside the range	Doesn't include it	Expands to include it

Microsoft also advises against listing single cells, like =SUM(A1,A2,A3,B1,B2,B3), because it has the same insert and delete problems. Use ranges instead: =SUM(A1:A3,B1:B3). And rather than typing long numbers straight into a formula, put them in cells and add the cells. It's far easier to check.

Summing only the visible rows in Excel

Filtering a list and expecting the total to change is a classic trap. SUM adds every cell in the range, hidden or not. Microsoft's answer is the SUBTOTAL function, which sums only the visible cells after you've hidden rows or used a filter.

That's useful when you filter a client list by month and want the total for just those rows. If you mainly keep your trackers in Google instead, my guide to adding up numbers in Google Sheets covers the same formula there.

Using AutoSum on the Excel phone app

On an Android phone or tablet, Microsoft's steps are:

1. Tap the first empty cell after your numbers, or drag to select the range.
2. Tap AutoSum, then tap Sum.
3. Tap the check mark.

Everyday ways to sum in Excel for small businesses

• Total hours per client at the bottom of a timesheet.
• Orders or units shipped for the week.
• New subscribers or followers across a run of weekly rows.
• Mileage or stock counts over a month of entries.

Pair a total with a tick column and you've got a simple progress tracker. My walkthrough of tick boxes in Google Sheets shows the browser-based version of that idea.

If your Excel sum is wrong or shows zero

1. Total too low? Some numbers may be stored as text, which SUM skips. Look for numbers aligned to the left of the cell.
2. Total includes hidden rows? Use SUBTOTAL instead of SUM.
3. Too many or too few decimal places? Press Ctrl+1 and change the format on the Number tab.
4. AutoSum picked the wrong cells? Drag over the right range before pressing Enter, or type the formula yourself.

Frequently asked questions

What's the quickest way to sum in Excel?

Click the cell under your column of numbers and select AutoSum on the Home tab, then press Enter. On Windows, Alt and the equals sign does the same.

How do I sum two separate ranges in Excel?

Separate them with a comma, as in Microsoft's example =SUM(A2:A10, C2:C10).

Why does my SUM ignore some numbers?

Microsoft says SUM ignores text values. If a number was stored as text, perhaps from an import, it won't be counted.

How do I sum only filtered rows in Excel?

Use the SUBTOTAL function. Microsoft says it sums only the visible cells after hiding rows or using AutoFilter.

How many numbers can one SUM formula add?

Microsoft says you can specify up to 255 numbers, cell references or ranges in one SUM.