Free Boating & Marine Calculators

Calculate fuel burn rate, cruising range, navigation, boat sizing, and ownership costs Calculate fuel costs, engine sizing, and marine measurements — all for free. No signup, no guesswork.

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Fuel & Range

Fuel burn rate, trip cost, cruising range, tank sizing, trolling consumption, MPG, annual fuel cost, and fuel flow calculators.

8 calculators

Navigation & Safety

Nautical mile converter, speed/distance/time, true wind, anchor rode, current drift, channel depth, wave height, and visibility calculators.

8 calculators

Boat Sizing & Capacity

Hull speed, displacement, max horsepower, trailer tongue weight, trailer capacity, boat capacity, and prop size calculators.

7 calculators

Ownership Costs

Annual cost of ownership, slip fees, winterization, insurance, boat loan payment, depreciation, and maintenance schedule calculators.

7 calculators

Popular Calculators

Fuel Burn Rate GPH Calculator

Calculate your boat engine fuel consumption in gallons per hour based on engine horsepower, RPM, and engine type. Know your burn rate before you leave the dock.

fuel-range

Fuel Cost Per Trip Calculator

Estimate fuel cost for a boat trip based on distance, fuel consumption rate, and current fuel price. Plan your budget before casting off.

fuel-range

Cruising Range Calculator

Calculate how far your boat can travel on a tank of fuel at various speeds. Factor in reserve requirements for safe trip planning.

fuel-range

Annual Fuel Cost Calculator

Estimate your total annual boat fuel expense based on usage patterns, trip frequency, and fuel consumption. Budget accurately for the season.

fuel-range

Nautical Mile Converter Calculator

Convert between nautical miles, statute miles, and kilometers. Essential for navigating between chart distances and GPS readings.

navigation

Speed Distance Time Calculator

Calculate speed, distance, or time for marine navigation. Enter any two values to find the third. Works in knots and nautical miles.

navigation

Anchor Rode Length Calculator

Calculate the proper anchor rode length (scope) based on water depth, tidal range, and conditions. Get the right scope for safe anchoring.

navigation

Wave Height Safety Calculator

Assess wave conditions for your boat size and type. Determine safe operating limits based on wind speed and fetch distance.

navigation

Hull Speed Calculator

Calculate the theoretical hull speed of a displacement boat based on waterline length. Understand the speed limit imposed by hull design.

sizing

Max Horsepower Calculator

Calculate the USCG maximum horsepower rating for your boat based on length, beam, and transom height. Stay within safe power limits.

sizing