Unit Converter
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 21 millimeters into kilometers we have to multiply 21 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
21 mm → L(km)
Solve the above proportion to obtain the length L in kilometers:
L(km) = 21 mm × 1.0E-6 km
L(km) = 2.1E-5 km
The final result is:
21 mm → 2.1E-5 km
We conclude that 21 millimeters is equivalent to 2.1E-5 kilometers:
21 millimeters = 2.1E-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 47619.047619048 × 21 millimeters.
Another way is saying that 21 millimeters is equal to 1 ÷ 47619.047619048 kilometers.
Approximate result
For practical purposes we can round our final result to an approximate numerical value. We can say that twenty-one millimeters is approximately zero kilometers:
21 mm ≅ 0 km
An alternative is also that one kilometer is approximately forty-seven thousand six hundred nineteen point zero four eight times twenty-one 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
millimeters (mm) | kilometers (km) |
---|---|
22 millimeters | 0 kilometers |
23 millimeters | 0 kilometers |
24 millimeters | 0 kilometers |
25 millimeters | 0 kilometers |
26 millimeters | 0 kilometers |
27 millimeters | 0 kilometers |
28 millimeters | 0 kilometers |
29 millimeters | 0 kilometers |
30 millimeters | 0 kilometers |
31 millimeters | 0 kilometers |