Parts of a Compass – Magnetic and Drawing Compass

All 10 parts on the diagram

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Baseplate compass 6

Base plate Its straight edge works as a ruler. It measures distances on a map.
Direction of travel arrow When walking on a bearing, follow this arrow, not the needle.
Rotating dial Also called the housing or the bezel. It shows the cardinal points and the degrees from 0 to 360, and it turns.
Magnetic needle One end points to magnetic north. The compass must be held level with nothing magnetic near.
Orienting arrow Used to take a bearing. The dial is turned until the needle lines up with it.
Orienting lines They run parallel to the orienting arrow. They can be lined up with the grid lines on a map.

Drawing compass 4

Handle Rolled between thumb and forefinger. That turns the compass to draw the circle.
Legs One leg carries the needle point and the other the pencil lead. Opening them wider draws a bigger circle.
Needle point It marks the center of the circle that is being drawn.
Pencil lead It draws the circle as the compass turns round the needle point.

How this list was compiled: Every name and detail checked on 2026-09-30. Baseplate compass: National Wildfire Coordinating Group, Basic Land Navigation (PMS 475), chapter 4, Parts of a Compass (magnetic needle, housing with its revolving dial, orienting arrow, orienting lines, index line, direction of travel arrow, base plate), https://fs-prod-nwcg.s3.us-gov-west-1.amazonaws.com/s3fs-public/publication/pms475.pdf, and Wikipedia, Compass (baseplate, rotating capsule, bezel or outer dial, orienting arrow, orienting lines, direction-of-travel indicator), text only. Drawing compass: Wikipedia, Compass (drawing tool) (handle, legs, hinge, needle point, pencil lead), text only, and Thomas E. French, A Manual of Engineering Drawing for Students and Draftsmen, 1918, public domain (handle, legs, needle point, lead), https://archive.org/details/amanualengineer00frengoog. Licence: own work

The drawing: Drawn for this site on 2026-09-30 from plain geometry; nothing traced. Licence: own work

How it works

What are the parts of a compass? It depends which compass you mean. The first drawing is a baseplate compass for finding your way. The second is the drawing compass used in geometry class.

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The compass that finds north

Numbers 1 to 6 are on a baseplate compass seen from above. The needle swings freely and one end points to magnetic north. The dial turns. The orienting arrow and the orienting lines are marked on the floor of the dial and turn with it.

The compass that draws circles

Numbers 7 to 10 are on a drawing compass. The needle point stays at the center while the pencil lead travels round it. Open the legs wider for a bigger circle.

Keep a magnetic compass away from steel and iron objects, which give a wrong reading.

Questions and answers

What are the parts of a compass?

A baseplate compass has a base plate, a direction of travel arrow, a rotating dial marked in degrees, a magnetic needle, an orienting arrow and orienting lines. A drawing compass has a handle, two legs, a needle point and a pencil lead.

Which way does a compass needle point?

One end of the magnetic needle, the marked end, points to magnetic north, provided the compass is held level and steady and nothing magnetic is nearby.

What is the orienting arrow on a compass?

The outlined arrow on the floor of the dial. To take a bearing, the dial is turned until the magnetic needle lines up with the orienting arrow. The bearing is then read where the dial meets the index line.

What are the parts of a drawing compass called?

Two legs joined at the top under a small handle. One leg ends in a needle point, which marks the center of the circle, and the other holds a pencil lead, which draws it.