Conversion formula

The conversion factor from kilometers per hour to knots is 0.53995680345662, which means that 1 kilometer per hour is equal to 0.53995680345662 knots:

1 km/h = 0.53995680345662 kt

To convert 640 kilometers per hour into knots we have to multiply 640 by the conversion factor in order to get the velocity amount from kilometers per hour to knots. We can also form a simple proportion to calculate the result:

1 km/h → 0.53995680345662 kt

640 km/h → V_(kt)

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

V_(kt) = 640 km/h × 0.53995680345662 kt

V_(kt) = 345.57235421224 kt

The final result is:

640 km/h → 345.57235421224 kt

We conclude that 640 kilometers per hour is equivalent to 345.57235421224 knots:

640 kilometers per hour = 345.57235421224 knots

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 knot is equal to 0.0028937499999952 × 640 kilometers per hour.

Another way is saying that 640 kilometers per hour is equal to 1 ÷ 0.0028937499999952 knots.

Approximate result

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

640 km/h ≅ 345.572 kt

An alternative is also that one knot is approximately zero point zero zero three times six hundred forty kilometers per hour.

Conversion table

kilometers per hour to knots chart

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