An array formula calculates across many values at once instead of only one value. Classic Excel array formulas are often entered with Ctrl+Shift+Enter and show curly braces in the formula bar after Excel accepts them.
Does this affect you?
Use this for current Excel versions and Excel 2019 or earlier when you see formulas wrapped in braces or instructions to press Ctrl+Shift+Enter. Microsoft 365 often handles newer dynamic arrays with normal Enter.
Enter a classic array formula
This is the traditional CSE method.
- Click the result cell.
- Type a formula that works across ranges, such as =SUM((A2:A100=”Open”)*(B2:B100)).
- Press Ctrl+Shift+Enter on Windows or Cmd+Shift+Enter on Mac instead of normal Enter.
- Check the formula bar. Excel adds curly braces around the formula automatically.
Do not type the braces yourself. They only mean Excel accepted the formula as an array formula.
Edit an array formula
Classic array formulas must be confirmed the same way after editing.
- Select the array formula cell.
- Edit the formula.
- Press Ctrl+Shift+Enter or Cmd+Shift+Enter again.
- Confirm the curly braces return in the formula bar.
More control
Modern dynamic arrays are different
Microsoft 365 functions such as FILTER, SORT, UNIQUE, and SEQUENCE spill results with normal Enter and usually do not need Ctrl+Shift+Enter.
Use SUMPRODUCT for some cases
For conditional sums across ranges, SUMPRODUCT often produces the same result with normal Enter, making it easier to maintain in older workbooks.
Fix wrong results
If a classic array formula gives the wrong result, it may have been entered with normal Enter or with ranges of different sizes. Recheck matching ranges and confirm with Ctrl+Shift+Enter.
Sources
- Microsoft Support – Create an array formula (2025)
- Microsoft Support – Guidelines and examples of array formulas (2024)
- Microsoft Support – Dynamic arrays and spilled array behavior (2025)