Marine & Boating
Hull Speed Calculator
Theoretical hull speed of a displacement boat from its waterline length.
hull speed (knots) = 1.34 × √(waterline l…
Also called displacement speed · boat hull speed
Auto & Travel · 8 calculators
Marine & Boating Calculators
Hull speed, fuel range and consumption, propeller slip, anchor scope, boat displacement and nautical miles.
Marine & Boating
Fuel Range Calculator
How far you can travel on the fuel aboard, with a safe reserve held back.
range = usable fuel ÷ burn rate × speed
Also called range on fuel · boat fuel range
Marine & Boating
Fuel Consumption Calculator
Fuel consumption from distance and fuel used, in L/100km, km/L and MPG, plus the cost.
L/100km = litres used ÷ distance × 100
Also called fuel efficiency calculator · litres per 100 km
Marine & Boating
Nautical Mile Converter
Convert nautical miles (nmi) to kilometers (km) instantly. Includes the exact conversion factor, formula and a quick reference table.
km = nmi × 1.852
Also called nmi to km · Nautical miles to Kilometers
Marine & Boating
Propeller Slip Calculator
Propeller slip percentage from pitch, engine RPM, gear ratio and actual boat speed.
slip % = (theoretical speed − actual spee…
Also called prop slip calculator · theoretical boat speed
Marine & Boating
Boat Displacement Calculator
Displacement of a hull from its dimensions and block coefficient, in tonnes and volume.
displacement = L × B × T × Cb × water den…
Also called hull displacement calculator · boat weight from dimensions
Marine & Boating
Anchor Scope Calculator
Anchor rode to let out for a given depth, with the scope ratio and swing circle.
rode = (depth + bow height + tidal rise) …
Also called anchor rode calculator · scope ratio
Marine & Boating
Travel Time Calculator
Journey time from distance and average speed, including stops — with the arrival time.
Time = distance ÷ speed + breaks
Also called time calculator distance speed · how long will it take to drive
Key marine & boating formulas
| Hull Speed | hull speed (knots) = 1.34 × √(waterline length in feet) |
|---|---|
| Fuel Range | range = usable fuel ÷ burn rate × speed |
| Fuel Consumption | L/100km = litres used ÷ distance × 100 |
| Nautical Mile Converter | km = nmi × 1.852 |
| Propeller Slip | slip % = (theoretical speed − actual speed) ÷ theoretical speed × 100 |
| Boat Displacement | displacement = L × B × T × Cb × water density |
| Anchor Scope | rode = (depth + bow height + tidal rise) × scope ratio |
| Travel Time | Time = distance ÷ speed + breaks |
Marine & Boating questions
Can a boat exceed hull speed?
A planing hull can, with enough power. A heavy displacement hull effectively cannot without an enormous power increase.
How many kilometers are in one nautical mile?
1 nmi equals 1.852 km.