The relationships between rectangular coordinates (x,y) and polar coordinates (R,t), using the figure below, are as follows:

y = R sin t and
x = R cos t

R^{2} = x^{2} + y^{2} and tan t = y/x

where the quadrant of angle t is determined by the signs of x and y.

An html 5 applet is used to calculate x and y knowing R and t. Angle t may be in degrees or radians.

How to use the calculator
1 - Enter angle t then R (positive). Depending on whether t is in degrees or radians, press the button "enter" that is in the same row.