Centimeter

The centimeter (symbol cm) is a unit of length in the metric system. It equals one hundredth of a meter (0.01 m) and is a decimal subunit derived from the meter. The name comes from the French centimètre, from centum meaning hundred. The centimeter is not an SI base unit, but it is accepted for use with the SI.

In everyday use, the centimeter is common for measuring small to moderate lengths—such as the width of objects, the height of a person in many countries, or the dimensions of household items. In science, the centimeter has historical use in the CGS system (centimeter–gram–second), though SI units based on the meter are standard in modern practice.

Conversions and relationships: 1 centimeter equals 10 millimeters; 100 centimeters equal 1 meter; 1 meter equals 100 centimeters. The centimeter is exactly defined relative to the meter, which today is defined by the speed of light. In inches, 1 centimeter equals exactly 0.3937007874 inches, so 1 inch equals 2.54 centimeters exactly. For larger scales, 100,000 centimeters equal 1 kilometer.

Summary: The centimeter provides a convenient unit for a wide range of everyday and scientific measurements, bridging practical dimensions with the higher-precision meter.