AutoSum in Excel: The Alt+= Shortcut Explained

The Excel AutoSum shortcut is Alt+= on Windows and ⌘+Shift+T on a Mac. It writes a SUM formula for you and guesses which numbers to add, so a column total takes two key presses. This guide shows how AutoSum decides on a range, how to total many columns at once, and when its guess is wrong.

What is the AutoSum shortcut in Excel?#

AutoSum is a button and a shortcut that inserts =SUM() with a range already filled in.

The button is also on the Formulas tab. It shows the Greek letter sigma (Σ), the maths symbol for "sum".

AutoSum doesn't create a special kind of formula. The result is a normal SUM, exactly what you'd get by typing it yourself. If SUM is new to you, read the beginner's guide to the SUM function or the SUM function reference first.

How to use AutoSum, step by step#

You use AutoSum from the empty cell where the total should go. Take this table:

1. Click C6, the empty cell under the costs.
2. Press Alt+= (Mac: ⌘+Shift+T).
3. Excel types =SUM(C2:C5) and shows a moving border around C2:C5.
4. Check that the border covers the right cells.
5. Press Enter. C6 shows 137,800.

Step 4 is the one people skip. AutoSum's guess is only a suggestion. If it is wrong, drag over the correct cells or type the range before you press Enter.

How does AutoSum choose the range?#

AutoSum looks for numbers above the selected cell first, then to the left if there are none above. It extends the range until it meets a cell that is empty or holds text.

That rule explains every surprising guess:

• A gap in the data. If C3 were empty, AutoSum in C6 would pick only C4:C5, because it stops at the blank. Look out for this in lists with missing values.
• A header that is a number. If the header in C1 were the year 2025 instead of "Costs", AutoSum would include it, because it's a number. Your total would be 2,025 too high.
• A row total. Click D2, at the end of a row of numbers, and AutoSum looks left. It picks B2:C2, the numbers to the left in that row.
• Filtered lists. If you have filtered the data, AutoSum writes SUBTOTAL(9, …) instead of SUM. SUBTOTAL adds only the rows you can see.

Total several columns at once#

Select every empty total cell first, then press the shortcut once. Excel writes a separate SUM in each cell.

1. Select B6:C6.
2. Press Alt+= (Mac: ⌘+Shift+T).
3. B6 becomes =SUM(B2:B5) with 220,600, and C6 becomes =SUM(C2:C5) with 137,800.

You don't need to press Enter in this case. Excel enters all the formulas straight away.

You can also total rows and columns together. Select the numbers plus the empty row below and the empty column to the right, for example B2:D6, and press the shortcut. Excel fills the bottom row with column totals and the right column with row totals, including a grand total in the corner.

More than SUM: Average, Count, Max and Min#

The small arrow next to the AutoSum button opens a short list: Sum, Average, Count Numbers, Max and Min. Each one works the same way, guessing the range above or to the left.

These options have no default shortcuts of their own, but they are quick to type once you know them. Learn what each one returns in AVERAGE, MIN and MAX with examples. When one value is far from the rest, the average can mislead you, and MEDIAN and MODE give a fairer "typical" value. To pull out the second-highest or the top three, see LARGE and SMALL for top-N values.

Common AutoSum problems#

Most AutoSum problems come from accepting a guess without checking it.

• Nothing happens on a Mac. In a web browser, ⌘+Shift+T reopens a closed tab, so the shortcut may not reach a browser-based spreadsheet. In the Excel for Mac app it inserts AutoSum. In a browser, type the SUM yourself or use the Σ button.
• The total includes itself. If you select the total cell as part of the range, you get a circular reference. Excel warns you, and the total usually shows 0. Keep the range above the total.
• The total is too low. Some values may be numbers stored as text, which SUM skips. See why your Excel total is wrong for the checks.
• Hidden rows are still added. SUM includes rows you have hidden by hand. To total only the visible rows, use SUBTOTAL, explained in SUBTOTAL: totals that ignore filtered rows.

Why AutoSum matters in a job test#

AutoSum is one of the fastest ways to look confident in front of an interviewer. A test sheet often asks for column totals first, and two key presses per total saves time for the harder tasks. It also shows you know the keyboard, not only the mouse. Totals and shortcuts like this are everyday work in admin and office jobs. If formulas are still new, start with how to write your first Excel formula.

Practise it#

The best way to make Alt+= automatic is to use it on real numbers. Practise SUM and AutoSum in a live spreadsheet: you'll total revenue by typing SUM, use AutoSum on the costs, and combine ranges and single cells with commas. Or try the exercise on this page first.