Square Inch to Square Kilometer Conversion Calculator: Free Online Tool

Convert square inches to square kilometers with our free online area converter.

From:

in²

Square Inch

To:

km²

Square Kilometer

How to Use the Calculator:

Enter the value you want to convert in the 'From' field (Square Inch).
The converted value in Square Kilometer will appear automatically in the 'To' field.
Use the dropdown menus to select different units within the Area category.
Click the swap button (⇌) to reverse the conversion direction.

How to Convert Square Inch to Square Kilometer

Converting Square Inch to Square Kilometer involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Square Inch = 6.4516e-10 square kilometers

Example Calculation:

Convert 10 square inches: 10 × 6.4516e-10 = 6.4516e-9 square kilometers

Note: Conversion factors can sometimes be rounded for display purposes. For precise calculations, always use the full factor or rely on the calculator above.

What is a Square Inch and a Square Kilometer?

The square inch (symbol: in², sq in) is an imperial and US customary unit of area. It represents the area of a square with sides that are each one inch long.

The square kilometer (symbol: km²) is a decimal multiple of the SI unit of area, the square meter. It represents the area of a square with sides that are each one kilometer long (1 km² = 1,000,000 m²).

Note: The Square Inch is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Square Kilometer belongs to the metric (SI) system.

History of the Square Inch and Square Kilometer

Derived from the inch, whose definition has varied historically but was standardized as 25.4 mm, the square inch became a common unit for small area measurements within the imperial system. It is frequently used in the US and UK for engineering and everyday measurements.

As a multiple of the square meter, the square kilometer came into use alongside the metric system for measuring large areas like land masses, cities, and countries. Its adoption followed the establishment of the kilometer as a standard unit of distance.

Common Uses for square inches and square kilometers

Explore the typical applications for both Square Inch (imperial/US) and Square Kilometer (metric) to understand their common contexts.

Common Uses for square inches

Engineering & Manufacturing (US/UK): Specifying the area of small components, cross-sections, or surface areas.
Material Measurement: Measuring the area of small sheets of material (e.g., paper, fabric samples).
Pressure Measurement: Used implicitly in units like pounds per square inch (psi).
Crafts & Hobbies: Measuring fabric squares, paper sizes, or small design areas.

Common Uses for square kilometers

Geography & Cartography: Standard unit for measuring the land area of cities, regions, countries, and continents.
Demographics: Used to calculate population density (people per km²).
Environmental Science: Measuring the extent of forests, deserts, lakes, or areas affected by environmental changes (e.g., deforestation, wildfires).
Urban Planning: Assessing land use and zoning areas within large municipalities.

Frequently Asked Questions

Questions About Square Inch (in²)

How many square inches are in a square foot?

There are 144 square inches in one square foot (12 inches x 12 inches).

How many square centimeters are in a square inch?

One square inch is equal to exactly 6.4516 square centimeters.

Is the square inch used for large areas?

No, it's used for small areas. Square feet (ft²) or square yards (yd²) are used for room sizes, and acres (ac) or square miles (mi²) for land.

Is the square inch an SI unit?

No, it is part of the imperial and US customary systems. The corresponding metric units are square centimeter (cm²) or square millimeter (mm²).

About Square Kilometer (km²)

How many square meters are in a square kilometer?

There are 1,000,000 square meters in one square kilometer (1 km x 1 km = 1000 m x 1000 m).

How many square miles are in a square kilometer?

One square kilometer is approximately 0.3861 square miles.

Is km² used for small areas?

No, it's generally used for very large areas like cities or countries. Square meters, hectares, or acres are used for smaller plots.

Is km² an official SI unit?

While based on the SI unit meter, the official SI derived unit for area is the square meter (m²). However, the square kilometer is a standard metric unit widely accepted for use with SI.

Conversion Table: Square Inch to Square Kilometer

Square Inch (in²)	Square Kilometer (km²)
1	0
5	0
10	0
25	0
50	0
100	0
500	0
1,000	0

All Area Conversions

Square Meter to Square Kilometer Square Meter to Square Centimeter Square Meter to Square Millimeter Square Meter to Square Inch Square Meter to Square Foot Square Meter to Square Yard Square Meter to Square Mile Square Meter to Acre Square Meter to Hectare Square Kilometer to Square Meter Square Kilometer to Square Centimeter Square Kilometer to Square Millimeter Square Kilometer to Square Inch Square Kilometer to Square Foot Square Kilometer to Square Yard Square Kilometer to Square Mile Square Kilometer to Acre Square Kilometer to Hectare Square Centimeter to Square Meter Square Centimeter to Square Kilometer Square Centimeter to Square Millimeter Square Centimeter to Square Inch Square Centimeter to Square Foot Square Centimeter to Square Yard Square Centimeter to Square Mile Square Centimeter to Acre Square Centimeter to Hectare Square Millimeter to Square Meter Square Millimeter to Square Kilometer Square Millimeter to Square Centimeter Square Millimeter to Square Inch Square Millimeter to Square Foot Square Millimeter to Square Yard Square Millimeter to Square Mile Square Millimeter to Acre Square Millimeter to Hectare Square Inch to Square Meter Square Inch to Square Centimeter Square Inch to Square Millimeter Square Inch to Square Foot Square Inch to Square Yard Square Inch to Square Mile Square Inch to Acre Square Inch to Hectare Square Foot to Square Meter Square Foot to Square Kilometer Square Foot to Square Centimeter Square Foot to Square Millimeter Square Foot to Square Inch Square Foot to Square Yard Square Foot to Square Mile Square Foot to Acre Square Foot to Hectare Square Yard to Square Meter Square Yard to Square Kilometer Square Yard to Square Centimeter Square Yard to Square Millimeter Square Yard to Square Inch Square Yard to Square Foot Square Yard to Square Mile Square Yard to Acre Square Yard to Hectare Square Mile to Square Meter Square Mile to Square Kilometer Square Mile to Square Centimeter Square Mile to Square Millimeter Square Mile to Square Inch Square Mile to Square Foot Square Mile to Square Yard Square Mile to Acre Square Mile to Hectare Acre to Square Meter Acre to Square Kilometer Acre to Square Centimeter Acre to Square Millimeter Acre to Square Inch Acre to Square Foot Acre to Square Yard Acre to Square Mile Acre to Hectare Hectare to Square Meter Hectare to Square Kilometer Hectare to Square Centimeter Hectare to Square Millimeter Hectare to Square Inch Hectare to Square Foot Hectare to Square Yard Hectare to Square Mile Hectare to Acre