# How to Use SIN Function

The sine of an angle is the ratio of the length of the opposite side to the length of the hypotenuse.

In excel, SIN function returns the sine of the given angle in radians.

Formula:

=SIN(number)

Explanations:

Number is required, the angle in radian that you want the sine value.

Cautions:

The number (angle) needs to be in radians. When the angle is in degrees, using the angle multiply PI()/180 to convert the angle to radians first.