Square Kilometers to Square Millimeters Converter

Enter the area in square kilometers below to convert it to square millimeters.

sq km
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Result in Square Millimeters:

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1 sq km = 1,000,000,000,000 sq mm
1 sq km = 10,000,000,000 sq cm
1 sq km = 1,000,000 sq m

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Joe is the creator of Inch Calculator and has over 20 years of experience in engineering and construction. He holds several degrees and certifications.

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How to Convert Square Kilometers to Square Millimeters

To convert a measurement in square kilometers to a measurement in square millimeters, multiply the area by the following conversion ratio: 1,000,000,000,000 square millimeters/square kilometer.

Since one square kilometer is equal to 1,000,000,000,000 square millimeters, you can use this simple formula to convert:

square millimeters = square kilometers × 1,000,000,000,000

The area in square millimeters is equal to the area in square kilometers multiplied by 1,000,000,000,000.

For example, here's how to convert 5 square kilometers to square millimeters using the formula above.

square millimeters = (5 sq km × 1,000,000,000,000) = 5,000,000,000,000 sq mm

How Many Square Millimeters Are in a Square Kilometer?

There are 1,000,000,000,000 square millimeters in a square kilometer, which is why we use this value in the formula above.

1 sq km = 1,000,000,000,000 sq mm

Square kilometers and square millimeters are both units used to measure area. Keep reading to learn more about each unit of measure.

What Is a Square Kilometer?

One square kilometer is equivalent to the area of a square with sides that are each 1 kilometer in length. One square kilometer is equal to 0.386102 square miles or 1,000,000 square meters.

The square kilometer, or square kilometre, is a multiple of the square meter, which is the SI derived unit for area. In the metric system, "kilo" is the prefix for thousands, or 103. A square kilometer is sometimes also referred to as a square km. Square kilometers can be abbreviated as sq km, and are also sometimes abbreviated as km². For example, 1 square kilometer can be written as 1 sq km or 1 km².

Learn more about square kilometers.

What Is a Square Millimeter?

One square millimeter is equivalent to the area of a square with edges that are each 1 millimeter in length. One square millimeter is equal to 0.00155 square inches or 1/100 of a square centimeter.

The square millimeter, or square millimetre, is a multiple of the square meter, which is the SI derived unit for area. In the metric system, "milli" is the prefix for thousandths, or 10-3. A square millimeter is sometimes also referred to as a square mm. Square millimeters can be abbreviated as sq mm, and are also sometimes abbreviated as mm². For example, 1 square millimeter can be written as 1 sq mm or 1 mm².

Learn more about square millimeters.

Square Kilometer to Square Millimeter Conversion Table

Table showing various square kilometer measurements converted to square millimeters.
Square Kilometers Square Millimeters
0.000000000001 sq km 1 sq mm
0.000000000002 sq km 2 sq mm
0.000000000003 sq km 3 sq mm
0.000000000004 sq km 4 sq mm
0.000000000005 sq km 5 sq mm
0.000000000006 sq km 6 sq mm
0.000000000007 sq km 7 sq mm
0.000000000008 sq km 8 sq mm
0.000000000009 sq km 9 sq mm
0.0000000000001 sq km 0.1 sq mm
0.000000000001 sq km 1 sq mm
0.00000000001 sq km 10 sq mm
0.0000000001 sq km 100 sq mm
0.000000001 sq km 1,000 sq mm
0.00000001 sq km 10,000 sq mm
0.0000001 sq km 100,000 sq mm
0.000001 sq km 1,000,000 sq mm
0.00001 sq km 10,000,000 sq mm
0.0001 sq km 100,000,000 sq mm
0.001 sq km 1,000,000,000 sq mm
0.01 sq km 10,000,000,000 sq mm
0.1 sq km 100,000,000,000 sq mm
1 sq km 1,000,000,000,000 sq mm

More Square Kilometer & Square Millimeter Conversions

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