Conversion formula

The conversion factor from millimeters to kilometers is 1.0E-6, which means that 1 millimeter is equal to 1.0E-6 kilometers:

1 mm = 1.0E-6 km

To convert 42 millimeters into kilometers we have to multiply 42 by the conversion factor in order to get the length amount from millimeters to kilometers. We can also form a simple proportion to calculate the result:

1 mm → 1.0E-6 km

42 mm → L_(km)

Solve the above proportion to obtain the length L in kilometers:

L_(km) = 42 mm × 1.0E-6 km

L_(km) = 4.2E-5 km

The final result is:

42 mm → 4.2E-5 km

We conclude that 42 millimeters is equivalent to 4.2E-5 kilometers:

42 millimeters = 4.2E-5 kilometers

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 kilometer is equal to 23809.523809524 × 42 millimeters.

Another way is saying that 42 millimeters is equal to 1 ÷ 23809.523809524 kilometers.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that forty-two millimeters is approximately zero kilometers:

42 mm ≅ 0 km

An alternative is also that one kilometer is approximately twenty-three thousand eight hundred nine point five two four times forty-two millimeters.

Conversion table

millimeters to kilometers chart

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