Divide the number of knots by 0.86896 to find the speed in miles per hour. For example, if the wind speed is 35 knots, divide 35 by 0.86896 to get 40.28 miles per hour.
Multiply the number of knots by 1.1508 to find the speed in miles per hour. In this example, multiply 35 by 1.1508 to get 40.28 miles per hour.
Check your answer with a knots-to-miles-per-hour converter (see Resources). Enter the number of knots and press "Convert to Miles Per Hour."