Motor and prop calculator ?
Enter the motor's Kv, the battery's cell count and the prop size to estimate current, power and thrust at full throttle. Add your ESC's rating to check it has enough headroom.
Result
Fill in the numbers above to see the result.
How it works
Under load a motor turns at roughly 85% of Kv × battery volts (3.7 V a cell).
The power a prop absorbs rises with the cube of RPM: watts = Kp × D⁴ × P × (RPM ÷ 1000)³, with diameter and pitch in feet and Kp about 1.25 for typical sport props. We allow for a motor that's about 80% efficient, so the battery current is that power ÷ 0.8 ÷ volts.
Thrust uses the same published formula as the prop thrust calculator. Props of the same size differ a lot, so treat the numbers as a starting point and confirm with a wattmeter - especially before going up a size.
Keep every model's numbers in one place
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