How to Square Root in Excel with Three Different Formulas

The SQRT function is the most well-known square root formula for Excel, primarily because its name is memorable. But what exactly is it, and how does it work?

What is SQRT in Excel?

Quite simply, the SQRT function returns a positive square root when you define a number or cell for it to analyze. It's important to note that if the value of the number is negative, you'll receive the “#NUM!” error. We'll teach you a way around this.

The SQRT formula syntax looks something like this: =SQRT(number). Here's how you can use it in your spreadsheets:

1. Type the formula into a cell
   

   In your Excel document, click on the cell where you want to display your result and type =SQRT(cell/number). You should replace cell/number with the cell or number you want to find the square root of.

   In our example, we have a number in the B2 column that we'd like to find the square root of, so our final formula will look like this: =SQRT(B2). If we didn't have the number in a separate cell, we could equally type the number directly: =SQRT(151). 

   Once you press Enter your result will display in your selected cell – in our case 12.28821.

   

2. Don't use SQRT directly with a negative number
   

   As mentioned earlier, using SQRT with a negative outcome will result in the #NUM! error. You can try this yourself by pointing it to a cell with a minus number. If you run into this error, you can remedy it by following the technique below.

   

3. Use ABS with SQRT to square root in Excel with any number
   

   Due to the issue with negative numbers, you should ideally always use the ABS function along with SQRT. ABS will convert a negative number to an absolute number so that SQRT can process it. Your final formula, then, would look something like this:

   =SQRT(ABS(B2))

   As you can see, it's still easy enough to remember, but can be used more universally.

   

Another way to find the square root of a number in Excel is the POWER function. Aside from the amusement factor of typing POWER in all caps, it works slightly differently.

What is POWER in Excel?

The POWER function differs from SQRT in that this formula for square root finds its answer by raising the specified number to the Nth power.

The POWER square root formula, therefore, takes two inputs: the number to raise to a power, and the power to raise the number to, also known as the exponent. If that still doesn't make sense, don't worry – you can check our example below.

1. Type the Square root POWER formula in your cell
   

   In the cell where you'd like the result to be displayed, type the following:

   =POWER(number/cell,power)

   You should replace number/cell with the number you want to find the square root of. power you can replace with 1/2 or half.

   Once you press Enter, the formula will return the square root of your specified number. This is because a square root is the same as a 1/2 exponent.

   This takes us nicely on to our next method, the exponent operator.

   

As we mentioned earlier, a half exponent is the same as a square root. We won't go into the why of this – instead, you can read up here.

What is the exponent operator in Excel?

The POWER function is one way to calculate a half exponent in Excel, but there's a way that doesn't require a formula at all – the exponent operator. It works similarly to POWER, raising a number to the Nth power, but is typically faster and easier to type. Here's how to square root in Excel with it:

1. Use the exponent operator with your number or cell
   

   Using the exponent operator is simple. In the cell where you want your result to display, type the following:

   =cell/number^(1/2)

   In our example, then, it would look like this:

   =B2^(1/2)

   After pressing Enter, you'll get your result.

   

   How to Find and Remove Duplicates in Excel or Combine Text Cells

   That's all there is to it. You now know how to square root in Excel. If you want to POWER up your Excel knowledge even further, though, you may want to check out some of our other tutorials. Why not learn how to combine text cells with concatenate or find duplicates and remove them?