太阳方位角是太阳在方位上的角度，它通常被定义为从北方延着地平线顺时针量度的角。

它可以利用下面的公式，经由计算得到良好的近似值，但是因为反正弦值，也就是x = sin(y)有两个以上的解，但只有一个是正确的，所以必需小心的处理。

下面的两个公式也可以用来计算近似的太阳方位角，不过因为公式是使用余弦函数，所以方位角永远是正值，因此，角度永远被解释为小于180度，而必须依据时角来修正。当在上午时角为负值时 (上午)，方位角的角度小于180度，时角为正值时 (下午)，方位角应该大于180度，即要取补角的值。(大于180度的角没有补角，读者慎重。)

The solar azimuth angle is the azimuth angle of the sun. It defines in which direction the sun is, whereas the solar zenith angle or its complementary angle solar elevation defines how high the sun is. There are several conventions for the solar azimuth, however it is traditionally defined as the angle between a line due south and the shadow cast by a vertical rod on Earth. This convention states the angle is positive if the line is east of south and negative if it is west of south. For example due east would be 90° and due west would be -90°. Another convention is the reverse; it also has the origin at due south, but measures angles clockwise, so that due east is now negative and west now positive.