Summary

The Excel SQRT function returns the square root of a positive number. SQRT returns an error if number is negative.

Purpose 

Find the positive square root of a number

Return value 

Positive square root

Arguments 

  • number - The number to get the square root of.

Syntax 

=SQRT(number)

How to use 

The Excel SQRT function returns the square root of a positive number. SQRT returns an error if number is negative.

The SQRT function takes one argument, number, which must be a numeric value. If number is not numeric, SQRT returns a #VALUE! error. If number is negative, SQRT returns a #NUM! error.

Examples

=SQRT(9) // returns 3
=SQRT(81) // returns 9
=SQRT(144) // returns 12
=SQRT(0.25) // returns 0.5
=SQRT(0) // returns 0

Negative numbers

The SQRT function will return a #NUM! error when number is negative:

=SQRT(-9) // returns #NUM!

To get the square root of a negative number (as if the number was positive), wrap the number in the ABS function like this:

=SQRT(ABS(-9)) // returns 3

Notes

  • If number is not numeric, SQRT returns a #VALUE! error.
  • If number is negative, SQRT returns a #NUM! error.
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Dave Bruns

Hi - I'm Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.