Excel SQRT function


The Excel SQRT function calculates the square root of a given number. It’s widely used in mathematical, engineering, and financial calculations, especially where the measurement of geometric or other properties involving squares is involved.
  • number: The number for which you want to find the square root. Note: If the number is negative, SQRT will return the #NUM! error
Return value
The square root of the specified number.

How to use

Use the SQRT function by inputting the number for which you wish to calculate the square root. This function is useful for a variety of scientific and mathematical calculations where the square root is needed.


Simple SQRT
Calculating the Square Root of a Number: To find the square root of 16:

This formula returns 4, which is the square root of 16.

SQRT in Geometry Calculations
Finding the Length of a Diagonal in a Square: Using SQRT to calculate the diagonal length of a square with side length 5:
					=SQRT(5^2 + 5^2)
This formula calculates the diagonal length of the square, which is approximately 7.07.
SQRT for Statistical Data
Standard Deviation Calculation: In statistics, SQRT is often used to calculate the standard deviation:
This calculates the standard deviation for a population based on the variance of values in A2:A10.
SQRT in Engineering
Engineering Applications: Using SQRT in more complex engineering formulas:
					=SQRT(Force / Area)
This formula might be used in engineering to calculate stress or pressure, where Force is divided by Area.
SQRT for Financial Models
Calculating Compound Interest: In finance, SQRT can be used to calculate compound interest over a square root time period:
					=Principal * (1 + InterestRate) ^ SQRT(Time)
This formula calculates the amount of compound interest on a principal amount over a square root time period.

Additional Notes

  • SQRT is an essential function in any calculation involving square roots, used in a wide array of scientific, engineering, and financial calculations.
  • If the input number is negative, SQRT returns the #NUM! error, as the square root of a negative number is not a real number.

Related Functions

Excel POWER function

The Excel POWER function raises a number to a specified power, essential for exponential growth calculations and geometric operations.

Content Navigation