Boxing the compass

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A 16-point compass rose

A 32-point compass rose

A historical compass card

Boxing the compass is the action of naming all thirty-two principal points of the compass in clockwise order. Such names, formed by the initials of the cardinal directions and their intermediate ordinal directions, are accepted internationally, even though they have their origin in the English language, and are very handy to refer to a heading (or course or azimuth) in a general or colloquial fashion, without having to resort to computing or recalling degrees.

The set of 32 named points can be further divided into a set of 128 named directions using quarter-points,^[1] although for communicating heading these fractional points have been superseded by degrees measured clockwise from North.

Contents [hide] 1 Compass points 2 See also 3 References 4 External links

[edit] Compass points

A simple algorithm can be used to convert a heading to an approximate compass point:

1. Divide the heading in degrees by 11.25 (360/32) to get to the case of 32 named points.
2. Add 1.5 to center the named points in their respective sectors on the circle, since north is 1 in the table instead of 0. If the result is 33 or more, subtract 32 to keep within the 32-point set.
3. Now look up the integer part of the result in the table below.

For example:

A heading of 75°, divided by 11.25 gives 6.67, added to 1.5 gives 8.17, truncated to give 8. 8 in the table below corresponds to east by north.

#	Compass point	Abbr.	Traditional wind point	Heading	Heading Range
1	North	N	Tramontana	0.00°	0.00 - 5.62°
2	North by east	NbE		11.25°	5.63 - 16.87°
3	North-northeast	NNE		22.50°	16.88 - 28.12°
4	Northeast by north	NEbN		33.75°	28.13 - 39.37°
5	Northeast	NE	Greco or Bora	45.00°	39.38 - 50.62°
6	Northeast by east	NEbE		56.25°	50.63 - 61.87°
7	East-northeast	ENE		67.50°	61.88 - 73.12°
8	East by north	EbN		78.75°	73.13 - 84.37°
9	East	E	Levante	90.00°	84.38 - 95.62°
10	East by south	EbS		101.25°	95.63 - 106.87°
11	East-southeast	ESE		112.50°	106.88 - 118.12°
12	Southeast by east	SEbE		123.75°	118.13 - 129.37°
13	Southeast	SE	Sirocco	135.00°	129.38 - 140.62°
14	Southeast by south	SEbS		146.25°	140.63 - 151.87°
15	South-southeast	SSE		157.50°	151.88 - 163.12°
16	South by east	SbE		168.75°	163.13 - 174.37°
17	South	S	Ostro	180.00°	174.38 - 185.62°
18	South by west	SbW		191.25°	185.63 - 196.87°
19	South-southwest	SSW		202.50°	196.88 - 208.12°
20	Southwest by south	SWbS		213.75°	208.13 - 219.37°
21	Southwest	SW	Libeccio	225.00°	219.38 - 230.62°
22	Southwest by west	SWbW		236.25°	230.63 - 241.87°
23	West-southwest	WSW		247.50°	241.88 - 253.12°
24	West by south	WbS		258.75°	253.13 - 264.37°
25	West	W	Poniente or Zephyrus	270.00°	264.38 - 275.62°
26	West by north	WbN		281.25°	275.63 - 286.87°
27	West-northwest	WNW		292.50°	286.88 - 298.12°
28	Northwest by west	NWbW		303.75°	298.13 - 309.37°
29	Northwest	NW	Mistral	315.00°	309.38 - 320.62°
30	Northwest by north	NWbN		326.25°	320.63 - 331.87°
31	North-northwest	NNW		337.50°	331.88 - 343.12°
32	North by west	NbW		348.75°	343.13 - 354.37°
1	North	N	Tramontana	360.00°	354.38 - 360.00°