Calculators
Stability calculator
Pick a boat from … measured hulls and see what its own dimensions say about stability — ballast ratio, capsize screening, and a ballast-only righting estimate. A real righting-arm curve needs a hull's lines and its vertical centre of gravity — measurements most boats never had taken. Where a number here is an estimate rather than a measurement, it says so next to the number.
Nothing picked yet.
m
m
m
m
kg
kg
m²
Derived
Each figure shows how it's worked out. Ballast is the field to watch: only about one hull in six carries a measured figure for it, so the ballast ratio and the ballast-only righting estimate are blank for most boats.