Square Centimeter to Square Kilometer Conversion Calculator: Free Online Tool

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

From:

Square Centimeter

To:

Square Kilometer

How to Use the Calculator:

Enter the value you want to convert in the 'From' field (Square Centimeter).
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 Centimeter to Square Kilometer

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

Formula:

1 Square Centimeter = 1.0000e-10 square kilometers

Example Calculation:

Convert 10 square centimeters: 10 × 1.0000e-10 = 1.0000e-9 square kilometers

Disclaimer: For Reference Only

These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.

Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.

What is a Square Centimeter and a Square Kilometer?

The square centimeter (symbol: cm² or sometimes sq cm) is a unit of area in the International System of Units (SI). It represents the area of a square whose sides measure exactly one centimeter in length.

One square centimeter is equal to:

1/10,000 of a square meter (m²)
100 square millimeters (mm²)
Approximately 0.155 square inches (in²)

It is a derived SI unit, formed by squaring the SI base unit of length, the meter (via the centimeter).

The Square Kilometer (symbol: km² or sq km) is a multiple of the square meter (m²), the base unit of area in the International System of Units (SI). It represents the area of a square whose sides measure exactly one kilometer (km) in length.

Key relationships:

1 km² = 1 kilometer × 1 kilometer
1 km = 1,000 meters (m)
Therefore, 1 km² = (1,000 m) × (1,000 m) = 1,000,000 square meters (m²)
1 km² = 100 hectares (ha) (since 1 hectare = 10,000 m²)

In terms of imperial/US customary units:

1 km² ≈ 0.3861 square miles (mi²)
1 km² ≈ 247.1 acres (ac)

Note: The Square Centimeter is part of the metric (SI) system, primarily used globally in science and trade. The Square Kilometer belongs to the metric (SI) system.

History of the Square Centimeter and Square Kilometer

Metric System Origins: The concept of the square centimeter naturally arose with the establishment of the metric system during the late 18th century in France. As the centimeter (one-hundredth of a meter) was defined as a convenient subunit of length, the square centimeter became the corresponding unit for small areas.
SI Adoption: With the formalization of the International System of Units (SI) in the mid-20th century, the square meter (m²) was established as the coherent derived unit for area. The square centimeter (cm²), as a direct subdivision (1 cm² = 10⁻⁴ m²), is an accepted SI unit commonly used for measuring smaller areas where the square meter would be impractically large.

Origin: The square kilometer is derived directly from the kilometer, a unit of length introduced as part of the metric system, which was developed in France during the late 18th century.
Metric System Adoption: The metric system, including the meter and its multiples like the kilometer, was created to provide a standardized, decimal-based system of measurement. As nations began adopting the metric system throughout the 19th and 20th centuries, the square kilometer naturally became the standard unit for expressing large geographical areas.
SI Standard: The International System of Units (SI), formally established in 1960, confirmed the square meter (m²) as the base unit of area. The square kilometer is a widely accepted and commonly used multiple of this base unit, consistent with SI prefixes.
Global Usage: Today, the square kilometer is the predominant unit used worldwide for measuring the land area of countries, large administrative regions, bodies of water, and other significant geographical features.

Common Uses for square centimeters and square kilometers

Explore the typical applications for both Square Centimeter (metric) and Square Kilometer (metric) to understand their common contexts.

Common Uses for square centimeters

The square centimeter is frequently used for measuring relatively small surface areas across various fields:

Science: Measuring the surface area of small biological samples (like leaves or petri dishes), cross-sectional areas in physics and materials science, and quantifying reaction surfaces in chemistry.
Medical Imaging: Commonly used to report the area of skin lesions, wounds, organ cross-sections, or regions of interest in MRI, CT, or ultrasound scans.
Education: A fundamental unit in teaching geometry, area calculation, and understanding metric conversions in schools.
Manufacturing & Design: Specifying the area of small components, electronic parts (like integrated circuits), adhesive patches, or surface coating requirements.
Photography: Sometimes used informally to refer to the approximate size of smaller image sensors.
Retail & Labeling: Used on packaging to indicate the size of small items like stickers, patches, or fabric samples.

Common Uses for square kilometers

The square kilometer is almost exclusively used for measuring large-scale areas:

Geography and Cartography: The standard unit for stating the land or surface area of countries, continents, large islands, administrative divisions (states, provinces), and major cities.
Demography: Essential for calculating population density, typically expressed as inhabitants per square kilometer (people/km²).
Environmental Science: Measuring the extent of large ecosystems (forests, deserts, wetlands), national parks, conservation areas, watersheds, ice sheets, or the area impacted by large-scale environmental events (e.g., oil spills, deforestation).
Urban Planning and Land Management: Quantifying large zones, districts, or total city area in regional planning.
Geology and Planetary Science: Measuring the surface area of large geological formations or the surface areas of planets, moons, and asteroids.
Military and Logistics: Defining large operational areas or zones.

It is too large for measuring individual properties, farms (hectares or acres are preferred), or room sizes (square meters or square feet are used).

Frequently Asked Questions

Questions About Square Centimeter (cm²)

How small is a square centimeter visually?

One square centimeter is the area of a square 1 cm by 1 cm. This is roughly:

The size of the nail on an adult human index finger.
Slightly smaller than a standard US postage stamp.
About the size of one face of a standard six-sided die.

How many square millimeters (mm²) are in a square centimeter (cm²)?

There are exactly 100 square millimeters (mm²) in one square centimeter (cm²). This is because 1 cm = 10 mm, so 1 cm² = (10 mm) × (10 mm) = 100 mm².

How many square centimeters (cm²) are in a square meter (m²)?

There are exactly 10,000 square centimeters (cm²) in one square meter (m²). This is because 1 m = 100 cm, so 1 m² = (100 cm) × (100 cm) = 10,000 cm².

How do you convert square centimeters (cm²) to square inches (in²)?

To convert square centimeters to square inches, multiply the value in cm² by approximately 0.155. For example, 10 cm² is roughly 1.55 in². Conversely, 1 square inch is approximately 6.4516 square centimeters.

Is the square centimeter (cm²) an SI unit?

Yes, the square centimeter (cm²) is a derived unit of area within the International System of Units (SI). While the coherent SI unit for area is the square meter (m²), the cm² (equal to 10⁻⁴ m²) is formed using an accepted SI prefix (centi-) and is widely used for convenience when measuring smaller areas.

When is cm² used instead of m²?

Square centimeters (cm²) are preferred when measuring areas significantly smaller than one square meter, where using m² would result in very small decimal numbers (e.g., 0.005 m²). It offers a more convenient scale for objects like small electronic components, biological samples, or details in medical images.

About Square Kilometer (km²)

How many square meters are in one square kilometer?

There are exactly 1,000,000 square meters (m²) in one square kilometer. This is calculated as 1,000 meters × 1,000 meters.

How many hectares are in one square kilometer?

There are exactly 100 hectares (ha) in one square kilometer. (1 km² = 1,000,000 m² and 1 ha = 10,000 m²).

How do you convert square kilometers to square miles?

To convert square kilometers to square miles, multiply the area in square kilometers by approximately 0.386102.

Conversion formula: Area [mi²] ≈ Area [km²] × 0.386102
Example: 100 km² ≈ 100 × 0.386102 mi² ≈ 38.61 mi²

Conversely, to convert square miles to square kilometers, multiply by approximately 2.58999.

1 mi² ≈ 2.59 km²

Is the square kilometer an official SI unit?

Strictly speaking, the official SI derived unit for area is the square meter (m²). However, the square kilometer (km²) is formed by combining an SI prefix (kilo-) with the SI base unit (meter) raised to the power of two, making it a standard and fully accepted multiple within the metric system and for use alongside SI units.

What is the difference between a kilometer and a square kilometer?

A kilometer (km) is a unit of length or distance (one dimension). A square kilometer (km²) is a unit of area (two dimensions), representing a square with sides of one kilometer each.

Conversion Table: Square Centimeter to Square Kilometer

Square Centimeter (cm²)	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 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 Kilometer 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