Free physics-based calculator

Is electric right for
your boat?

Range anxiety, system sizing, and total cost: answered with real numbers built for your boat, not a generic spec sheet.

Free. No signup. About 2 minutes.

Built on ITTC-1957 friction, Froude number wave-making, and Crouch planing analysis.

An electric motor's spec sheet gives you one number: max power output. But you'll rarely run your motor at max power. You'll run it at whatever speed actually gets you to the cove, the marina, or the fishing spot you go to. What matters is how long the motor lasts at that speed, on the trips you actually take, not how powerful it is at full throttle.

Battery capacity, motor draw, hull resistance, and your typical trip length all interact, and most boat owners have no way to combine them into one personal answer. So the conversion stays theoretical: "electric could probably work," with no way to know if it'll actually cover your regular run, your favorite fishing spot, or that weekend trip you do every summer.

This site exists to turn "probably" into a number. Tell the calculator your boat, your motor and battery choice, and how you actually use it, and you'll get a personalized answer: the range and run time you can expect at the power level you'll really be running, not just the max-power figure on the spec sheet.

How the calculator works

Built from your boat's actual physics

We model the power your hull and motor draw at your target speed, convert that into energy use, and divide by your battery's capacity, turning your motor's max-power spec into a real answer for the speed you'll actually run.

Sized to your boat, not a generic chart

Enter your boat's specs and how you actually use it, and get a personalized battery size and range estimate back in minutes. No spreadsheet.

See it on the water, not just on paper

Mark where you launch and the spots you actually go, and see your reachable range plotted right on a map, so you know whether your battery and motor combo gets you to your fishing spot and back.

Will an electric motor actually have enough power for my boat?

That depends on your boat and how you use it. A motor's spec sheet lists max power output, but your hull, weight, and typical speed determine how much of that power you actually need. Run the numbers for your specific setup and you'll know, instead of guessing.

How much does an electric conversion actually cost?

It depends on your boat size, the battery capacity you need, and the motor you choose. The calculator's job is to tell you the battery size you actually need, so you're not paying for capacity you'll never use.

Why not just use the range number on the motor's spec sheet?

Because that number is max power output, and you'll almost never run your motor flat out. It comes down to the power level you'll use on your typical trip, and how long your battery lasts at that level. The calculator answers that for your boat and your use, instead of leaving you to do the math from one spec-sheet figure.

How long does this take, and how accurate is it really?

About 2 minutes, no signup. The model assumes calm water (no wind or current), so treat the result as your baseline range at a given power level, not a hard guarantee. Wind, current, and load will move the real number around, the same way they'd move a gas engine's fuel burn.

From the blog

Practical guides for boat owners thinking about going electric.

Jun 24, 2026

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