Toolbox
Twenty tools. One boat profile.
Standard published methods, inputs and assumptions printed with every result, and no tool goes live until it is checked against known cases.
Boat profileNot set. Add the boat, engine and gearbox once; every tool reads them.
Add my boatPropulsion
From the prop to the repower.
P-01Free · Pro
Propeller calculator
Right D × P, blades, blade area; over/underpropped verdictOpenP-02Free
P-03ProOutboard prop selector
Pitch for the full-throttle window, options across brandsComing soonSea-trial analyzer
From measured rpm and speed: real slip, how far off rated, what to changeOpenP-04Pro
Repower calculator
New engine in an old boat: gear ratio, prop, expected speedComing soonP-05Pro
Gear ratio picker
Which reduction ratio fits engine, prop aperture and speedComing soonP-06Free
Speed and power
Power for a target speed; hull speed; displacement vs planingComing soonP-07Free · Pro
P-08ProFuel use and range
Litres per hour and range at each rpm and speedComing soonCavitation check
Is the prop cavitating; minimum blade area; blade loadingOpenP-09ProBollard pull
Static thrust for tugs, workboats and fishing boatsOpenP-10Free · Pro
Electric repower
Motor kW, battery kWh and range for an electric conversionComing soonEngine room
Shafts, exhaust, air and fuel.
E-01Pro
Shaft and bearings
Shaft diameter for power and rpm; max distance between bearingsComing soonE-02Pro
Wet exhaust and raw water
Hose size, back pressure, raw-water flowComing soonE-03Pro
Engine room air
Intake and fan size for combustion and cooling airComing soonE-04Free
Fuel tank and lines
Tank capacity from dimensions; fuel line size for flowComing soonElectrical
Cables, batteries and charging.
L-01Free
Wire size and voltage drop
Cable cross-section for load, length and allowed drop at 12/24 VOpenL-02Free
Battery, alternator, solar
Bank size, charge source and solar for daily consumptionComing soonDeck and hull
Thrusters, anchors, paint and trailers.
H-01Free · Pro
Thruster sizing
Thruster kgf for length, windage and wind speedComing soonH-02Free
Anchor, chain and rode
Anchor weight, chain size and scopeComing soonH-03Free
Antifouling and bottom area
Wetted area and paint quantityComing soonH-04Free