Work out the port and starboard layline bearings to a windward mark, and see how many degrees you still need to sail before reaching one.
Check the VMG calculator for your boat's optimal beating angle at the current wind speed.
Status
50°
still to sail
Starboard Layline
320°
Port Layline
40°
The layline is the bearing on which, sailing closehauled, you fetch the mark without another tack. Below the layline, your bearing to the mark is still closer to dead upwind than your closehauled course — keep sailing. Past it, you've overstood and are sailing extra distance you didn't need to.
Assumes a fixed beat angle and no current or leeway. Real laylines shift with wind shifts and current — treat this as a starting estimate, not a substitute for watching the mark.
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Nautical and metric conversions
Wind speed and Beaufort scale
NATO alphabet and text converter
Interactive nautical charts
European weather and wind maps
Sailing optimization guide
True and apparent wind, visualized
Optimal upwind and downwind angles
Distress call generator
Course conversion, leeway, and current triangle
Calculate anchor rode length and scope
IMO FAL Form 5 crew list generator
Draw your boat layout with boat symbols, export as SVG
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