Use this sailing calculation as a planning or educational cross-check for navigation, wind and current, rig loads, stability, anchoring, tides, visibility, performance, or recovery under explicitly stated conditions.

Lateral offset (nm)

Perpendicular offset from the mark bearing.

Tack angle (°)

Angle between the course and the layline.

Compute the distance along a layline to the mark given the lateral offset and tack angle. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Distance (nm)

Distance to sail along the layline.

• Actual conditions change with vessel design and loading, sea state, wind, current, tide datum, weather, chart accuracy, equipment, crew, regulations, and safety margins. Simplified formulas do not replace seamanship, approved stability data, or current navigation information.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Cross-check official charts, tide and weather services, instrument data, vessel manuals, and collision regulations; maintain conservative margins and a safe alternative plan.

• Distance to Layline Calculator

  Calculate the distance along the course centerline to a layline from the lateral offset and half of the total angle between port and starboard tacks.

• Tack Distance Calculator

  Compute the distance sailed on one tack to cover a given lateral offset.

• Gybe Distance Calculator

  Compute the distance sailed during a gybe to cover a given lateral offset.