Compass Navigation: Bearings, Declination & Route Finding | Survival Solutions Offline: Download guide (.txt) Entire site (.zip) Navigation & Field Mapmaking Field principle A compass is a direction tool, not a position finder. Combine it with a map, terrain, distance and checkpoints to avoid confidently walking the wrong route. Quick visual reference. Read the explanations and limitations before use. On this page 1. Identify the compass parts 2. Take a bearing to a landmark 3. Convert magnetic and true bearings 4. Orient a map and measure direction 5. Avoid common errors Reference 1 of 5 Identify the compass parts Baseplate: Clear edge and direction-of-travel arrow align a map route with the compass. Rotating bezel: Degree ring for reading and setting a bearing, usually 0–360 degrees clockwise. Magnetic needle: The north-seeking end points toward magnetic north when the compass is level and clear of interference. Orienting lines: Parallel lines inside the bezel that align with map grid north lines. Back to top ↑ Reference 2 of 5 Take a bearing to a landmark 1. Aim: Hold the compass level, direction-of-travel arrow aimed at a distant distinct landmark. 2. Set: Rotate the bezel until its orienting arrow aligns under the north-seeking needle. 3. Read: Read degrees at the direction-of-travel index, not at the needle tip. 4. Travel: Choose a close intermediate landmark along that bearing and walk to it; repeat the check. Back to top ↑ Reference 3 of 5 Convert magnetic and true bearings Know the datum: True north, magnetic north and map grid north differ. Read the map legend and its north arrows. Use the current declination: When east is positive and west negative: TRUE bearing = MAGNETIC bearing + declination; normalize 0–359 degrees. Example: A 70° magnetic bearing at +4° east declination becomes approximately 74° true. A 70° magnetic bearing at −4° west becomes 66° true. Reverse: Magnetic bearing = true bearing − declination. Do not correct twice when using an already-adjusted declination compass. Check location/date: Declination varies with location and time; older printed map values can be wrong. Back to top ↑ Reference 4 of 5 Orient a map and measure direction Find the north reference: Read map north, grid north, scale and contour interval; use matching north references consistently. Align the map: Place compass on the map, adjust for declination, and rotate map and compass until the needle aligns with the orienting arrow. Set a course: Join your current known point to a destination; place baseplate edge along the course and rotate bezel until its north lines parallel the map grid. Cross-check: Compare expected terrain features, path junctions and crossings. Do not follow a bearing blindly across hazards. Back to top ↑ Reference 5 of 5 Avoid common errors Metal and electronics: Move away from vehicles, steel structures, magnets, phones and electrical equipment while taking a reading. Reverse-bearing confusion: A back bearing is 180° opposite the forward bearing (add or subtract 180°). Check before retracing. Lost position: Stop, shelter if necessary, identify last known location, retrace only when safe, and use emergency communications if in danger. Practice first: Test on a known route in daylight, using more than one visible checkpoint. Back to top ↑ Further reading & source material Use these sources to validate local rules, technical standards and updates. No emergency article replaces official alerts or trained responders. NOAA — Magnetic declination and bearings USGS — Orient a map with a compass Related quick references Related field guide Field mapmaking Open guide → Related field guide Map symbols quick reference Open guide → Back to Navigation & Field Mapmaking