Millimeters (mm) to Kilometers (km) Converter

How many millimeters (mm) are in 1 kilometer (km)? What is the formula for how to convert millimeters to kilometers (mm to km)?

1 millimeter (mm) = 0.000001 kilometer (km)
So we can say that there is 0.000001 kilometer in 1 millimeter.
This means that the multiplication conversion factor to convert a quantity expressed in a millimeter unit of measurement to an equivalent quantity expressed in a kilometer unit of measurement is 0.000001.

Inversely (or reciprocally),

1 kilometer (km) = 1,000,000 millimeters (mm)
So we can say that there are 1,000,000 millimeters in 1 kilometer.
This means that the division conversion factor to convert a quantity expressed in a millimeter unit of measurement to an equivalent quantity expressed in a kilometer unit of measurement is 1,000,000.

Knowing this inverse mathematical relationship between the two conversion factors and their reciprocal operations, we can derive two formulas to calculate and convert a quantity of length expressed in millimeters to an equivalent quantity of length expressed in kilometers (mm to km). Both formulas will yield the same result. The formulas are:

km = mm × 0.000001    → This is the formula based on the multiplication conversion factor.

and

km = mm ÷ 1,000,000    → This is the formula based on the division conversion factor.

For example, if you have a length of 85.5 millimeters that you want to convert to kilometers, you would use either of the two formulas as follows:

km = 85.5 mm × 0.000001 = 0.0000855 km

km = 85.5 mm ÷ 1,000,000 = 0.0000855 km

So, the result is the same using either formula, which is 0.0000855 kilometer.

Millimeters to kilometers (mm to km) conversion chart

To save you time and effort spent on having to perform manual calculations or look up conversion formulas every time a conversion from millimeters to kilometers is needed, here is a millimeters-to-kilometers conversion chart for your quick and easy reference. This conversion chart (or conversion table) shows common measurement values of length in millimeters and their equivalent measurement values in kilometers. These equivalent measurement values may be rounded off to 1 or 2 decimal places when it is mathematically expedient for everyday applications.

Conversion factor of 1 millimeter to other units of length

Here is a reference list providing a conversion of 1 millimeter (mm) to its equivalent values in various units of length, both metric and imperial:

What is a millimeter (mm)?

Definition of millimeter: A millimeter is a unit of length in the International System of Units (SI). It is equivalent to one thousandth of a meter (10^-3 m). It is commonly used for precisely measuring small lengths and dimensions such as mechanical parts in engineering and manufacturing.

The abbreviation for millimeter is mm. The single Unicode character ㎜ (U+339C) represents the 2-character Latin abbreviation for millimeter. The Windows Alt code for this character ㎜ is Alt + 13212.

What is a kilometer (km)?

Definition of kilometer: A kilometer is a unit of length in the International System of Units (SI), commonly known as the metric system, equal to one thousand meters (10^3 m). It is commonly used for longer distances, such as races, road distances and geographical features.

The abbreviation for kilometer is km. The single Unicode character ㎞ (U+339E) represents the 2-character Latin abbreviation for kilometer. The Windows Alt code for this character ㎞ is Alt + 13214.