Conversion formula

The conversion factor from miles per hour to knots is 0.8689762419014, which means that 1 mile per hour is equal to 0.8689762419014 knots:

1 mph = 0.8689762419014 kt

To convert 421.5 miles per hour into knots we have to multiply 421.5 by the conversion factor in order to get the velocity amount from miles per hour to knots. We can also form a simple proportion to calculate the result:

1 mph → 0.8689762419014 kt

421.5 mph → V_(kt)

Solve the above proportion to obtain the velocity V in knots:

V_(kt) = 421.5 mph × 0.8689762419014 kt

V_(kt) = 366.27348596144 kt

The final result is:

421.5 mph → 366.27348596144 kt

We conclude that 421.5 miles per hour is equivalent to 366.27348596144 knots:

421.5 miles per hour = 366.27348596144 knots

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 knot is equal to 0.0027302003511804 × 421.5 miles per hour.

Another way is saying that 421.5 miles per hour is equal to 1 ÷ 0.0027302003511804 knots.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that four hundred twenty-one point five miles per hour is approximately three hundred sixty-six point two seven three knots:

421.5 mph ≅ 366.273 kt

An alternative is also that one knot is approximately zero point zero zero three times four hundred twenty-one point five miles per hour.

Conversion table

miles per hour to knots chart

For quick reference purposes, below is the conversion table you can use to convert from miles per hour to knots