Catamaran Hull Speed Calculator


The catamaran hull speed calculator estimates the theoretical maximum cruising speed of a multihull vessel. Unlike monohulls, which are constrained by the traditional 1.34 displacement constant, catamarans utilize slender hulls to "punch through" bow wave resistance, unlocking significantly higher speed potentials.

Imperial (Feet) Metric (Meters)
Displacement length at the waterline.
Hull fineness and displacement weight profile.

Performance Results

Theoretical Hull Speed
(Nautical Miles per Hour)
Speed Equivalent
(Miles per Hour)

Why Catamarans are Faster

In naval architecture, monohulls are governed by the "Square Root of LWL" rule (Speed = 1.34 × √LWL). As they approach the speed of their own bow wave, wave resistance increases exponentially. Catamarans bypass this barrier because their individual sponsons/hulls are extremely slender, having length-to-beam (L/B) ratios of 10:1 or greater.

The "Hull Constant" Explained

  • Cruising Cat (1.55): Designed for heavy payloads (water tanks, generators, liveaboard gear, tender). They sit deeper and have more wetted surface area.
  • Performance Cat (1.75): Optimized hull shapes with wave-piercing bows, lighter displacement, and reduced wetted surface. These boats easily exceed standard displacement speed limiters.
  • Racing Cat (2.10+): Ultralight composite construction, deep daggerboards, and high sail-area-to-displacement ratios.

Real-World Performance Factors

Calculated hull speed represents theoretical potential under optimal wind and sea conditions. Actual speeds vary based on total gross displacement weight, sail power, hull cleanliness, and sea state.