SQL Server SQRT() Function

SQRT() returns the square root of a numeric expression as a float. The input must be a float or a type that SQL Server can implicitly convert to float. See Microsoft’s SQRT() reference.

Syntax

SQRT(float_expression)

float_expression is the value whose square root SQL Server calculates. The result type is float.

Examples

The input can be an integer or decimal value; SQL Server converts it to float and returns a floating-point result:

SELECT SQRT(9) AS exact_root,
       SQRT(2) AS approximate_root;

Use SQRT() when the formula requires a square root. For exponentiation, see POWER().