## Conversion formula

The conversion factor from kilometers to millimeters is 1000000, which means that 1 kilometer is equal to 1000000 millimeters:

1 km = 1000000 mm

To convert 4 kilometers into millimeters we have to multiply 4 by the conversion factor in order to get the length amount from kilometers to millimeters. We can also form a simple proportion to calculate the result:

1 km → 1000000 mm

4 km → L(mm)

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

L(mm) = 4 km × 1000000 mm

L(mm) = 4000000 mm

The final result is:

4 km → 4000000 mm

We conclude that 4 kilometers is equivalent to 4000000 millimeters:

4 kilometers = 4000000 millimeters

## Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 millimeter is equal to 2.5E-7 × 4 kilometers.

Another way is saying that 4 kilometers is equal to 1 ÷ 2.5E-7 millimeters.

## Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that four kilometers is approximately four million millimeters:

4 km ≅ 4000000 mm

An alternative is also that one millimeter is approximately zero times four kilometers.

## Conversion table

### kilometers to millimeters chart

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

kilometers (km) millimeters (mm)
5 kilometers 5000000 millimeters
6 kilometers 6000000 millimeters
7 kilometers 7000000 millimeters
8 kilometers 8000000 millimeters
9 kilometers 9000000 millimeters
10 kilometers 10000000 millimeters
11 kilometers 11000000 millimeters
12 kilometers 12000000 millimeters
13 kilometers 13000000 millimeters
14 kilometers 14000000 millimeters