The various types of compasses for orienteering and their distinct variations include:

1. Thumb Compasses

The preferred choice for foot orienteering, urban sprints, and highly technical forest terrain. They are strapped directly to your hand/thumb, allowing you to keep the compass aligned with your map without altering your grip. [1, 2]

• Fixed Capsule (No Bezel): The most popular style for advanced orienteers. They have no degrees or rotating housing, offering a clear, distraction-free view of the map. [1]
• Rotating Capsule: Features a standard 360-degree dial for dialling in specific bearings, offering a blend of traditional baseplate navigation and thumb compass speed. [1, 2]
• Stability Variations: Different models (such as the Silva Arc Jet collection) feature different needle types (e.g., rapid jet needles) to prevent wobble while running at high speeds. [1, 2, 3, 4]

2. Baseplate (or Protractor) Compasses

Best for beginners, training, and scouts. These consist of a rectangular, transparent plastic baseplate with printed lines, measuring scales, and a rotating compass dial. [1, 2, 3, 4]

• Standard Baseplate: Entry-level models (like the Suunto A-10 NH Compass or the Silva Field MS Compass) designed to easily lay flat on a map to determine bearings and plot routes. [1, 2, 3, 4, 5]
• Global Needle Compasses: Standard baseplate compasses balanced to function in all magnetic zones of the world, rather than just in the Northern or Southern hemispheres. [1, 2]

3. Sighting / Mirror Compasses

Used primarily for precise, long-distance navigation or open-terrain orienteering where you need to sight a distant landmark. [1, 2, 3, 4]

• Mirrored Baseplate: Functions identically to a standard baseplate but includes a hinged mirror with a sighting notch. It allows you to align the compass with a distant object in the real world while simultaneously reading the exact degree dial in the mirror’s reflection. Popular models in this range include the Silva Ranger S and Silva Expedition S. [1, 2, 3]

Key Design Variables (Sub-types)

When picking an orienteering compass, you will also need to consider these physical and geographical variations: [1, 2]

• Magnetic Balancing: Compasses are usually geographically calibrated. You must choose an orienteering compass balanced for your specific location (e.g., the UK) or a "global" needle if you travel. [1, 2]
• Left-Handed vs. Right-Handed: Thumb compasses come in both orientations. Most right-handed orienteers wear the thumb compass on their left hand (leaving their right hand free for punching controls and folding maps), so left-handed thumb compasses are the most common. [1, 2]
• Needle Width and Damping: High-speed orienteers may use needles specifically dampened (usually via viscous fluid inside the capsule) to stop vibrations and needle spinning as they run. [1, 2]