When using Microsoft Excel, you may come across curly braces { } in some formulas. These are used in array formulas. While not the most common of Excel formulas, array formulas provide useful information and curly braces make it clear that data is being used as an array formula.
What is an Array Formula?

An array formula works with an array of data rather than just a single piece of data.
Creating an Array Formula

While the variety of different array formulas possible is beyond the scope of this article, the keyboard function that establishes a formula as an array formula is CTRL+SHIFT+ENTER instead of just ENTER. This puts the curly braces around the formula.
Indentifying Array Formulas

The difference in appearance between a regular formula and an array formula is the curly braces. For instance, the function "=ROW(A1:A5)" would become "{=ROW(A1:A5)}" when a user inputs CTRL+SHIFT+ENTER instead of just ENTER following the formula entry.
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