This calculator allows you to enter direction angle, either in DMS (degrees, minutes, and seconds) or decimal degrees and outputs closest to the compass point for different compass roses. Additionally, it outputs bearing to the closest quarter-point of the compass.
Supported compass roses are
- Cardinal, with 4 cardinal points: north, south, east, west
- Intercardinal, with 8 points, 4 cardinal + 4 ordinals (NE, SE, SW, NW)
- Meteorological, with 16 points, 8 intercardinal + intermediate points between cardinal and ordinal points, such as north-northeast (NNE)
Mariner has 32 points, 16 + points such as northeast by north (NEbN) between north-northeast and northeast.
- Mariner, with 128 points, extended the 32-point system with half-and quarter-points to allow 128 directions.
Here is the picture of a 32-wind compass rose
The calculator produces a table row for each compass rose. The columns are:
- compass rose name
- point name, if this point has it (half- and quarter-points do not have names). The traditional point name is displayed after the slash if it exists. Seafarers in the Mediterranean Sea during the Middle Ages invented the 8-, 16- and 32-wind roses; thus, wind names were expressed in Italian (sort-of). For example, the traditional name for southeast is Scirocco (or Exaloc).
- value for fractional-point bearings increasing in the clockwise direction (CW)
- value for fractional-point bearings increasing in the counterclockwise direction (CCW)
- value which avoids the use of "by" with fractional points (No "by")
- value which corresponds to the system used by US Navy
- value which corresponds to the system used by Royal Navy
These five values are just different naming conventions for fractional compass points.
The last column displays the DMS value for the compass point.
More about points of the compass can be found here