Boat Speed Calculator

Find hull speed in knots.

Hull speed (knots) 6.7

Formula: hull speed = 1.34·√LWL

Step-by-step with your numbers:

1. Values used:

2. Waterline length = 25

4. Hull speed = 6.7knots

Did we solve your problem today?

Displacement hull speed is roughly 1.34 × √waterline length.

The math behind it

hull speed (knots) = 1.34 × √(waterline length in ft).

25 ft → 6.7 kn.

Planing hulls?

They can exceed hull speed by rising onto the plane.