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.

KB (ft)

Vertical distance from keel to center of buoyancy.

BM (ft)

Vertical distance from center of buoyancy to metacenter.

KG (ft)

Vertical distance from keel to center of gravity.

Compute the metacentric height using metacentricHeightFeet = keelToCenterBuoyancyFeet + buoyancyToMetacenterFeet - keelToCenterGravityFeet (GM = KB + BM - KG). 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]

Metacentric height (ft)

Metacentric height GM; negative values indicate unstable equilibrium.

• 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.

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