Where this fits
- Day Skipperrelevant
- Coastal Skipperrelevant
- Yachtmasterrelevant
Free compass workbench
Use a compass without losing the reference frame
Practice true, magnetic, and compass bearings with variation, deviation, hand-bearing lines, and a simple chart fix. It is an independent revision aid, not official RYA training or assessment.
Direct answer
A compass bearing must be labelled as true, magnetic, or compass. Convert between them by applying variation and deviation with the correct sign, then use hand-bearing position lines on the chart to check or fix your position.
- Best for
- True, magnetic, compass, variation, deviation
- Includes
- Conversion, bearing-source, and plotting modes
- Practice mode
- Reference-frame workbench and quiz
- Cost
- Free, no login required
True, magnetic, compass
Compass workbench
Convert headings, choose the source of a bearing, then plot only True position lines on the chart.
Variation arc
3.0° W
Deviation arc
2.3° W
True
016 T
Magnetic
019 M
Compass
021 C
Chart variation
Current variation
3.0° W
Location/date property.
Deviation for this steering compass
Deviation varies with compass heading. This card belongs to this vessel/compass set-up.
021 C uses 2.3° W
Uncorrecting: True to Compass
True -> Magnetic -> Compass
016 T- variation019 M- deviation021 C
Uncorrecting towards Compass: add West, subtract East.
Link to this tool
Use this canonical URL in club newsletters, lesson notes, or student revision plans.