Weldon MarineBoating calculators
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Calculator 4 of 4 · free

Prop slip

How fast your propeller would push the boat if it screwed through the water like a bolt through a nut, and how much of that you lose to slip.

Tip: a free Boat Card remembers your boat's numbers and fills these in.

Usually the second number stamped on the prop: 14 1/4 x 19 means 19.
From your engine or lower unit manual.
Clear

Example: 4,000 RPM, 19-inch pitch, 1.86:1, 34 mph by GPS.

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