How to calculate bearing in surveying?

Bearings are expressed in two ways:

1. Whole circle bearings (WCB)
2. Quadrantal bearings (QB)

Measurement of Whole circle bearing (WCB): The angle is measured with respect to the north direction in the clockwise direction and can be valued up to 360 degrees.

Measurement of Quadrantal bearing (QB):  The angle is measured with respect to the north and the south direction in the clockwise and anti-clockwise directions and can be valued up to 90 degrees.

Reduced bearing:  The whole circle bearing when expressed in Quadrantal bearing is known as a Reduced bearing.

Conversion formula for WCB to QB

(0 to 90) : same as WCB

(90 to 180) : 180 – WCB

(180 to 270) : WCB – 180

(270 to 360) : 360 – WCB

Fore and Back Bearing:

If the fore bearing is less than 180,

Back Bearing (BB) = Fore Bearing (FB) + 180

If the fore bearing is greater than 180,

Back Bearing (BB) = Fore Bearing (FB) – 180