A square millimeter (often abbreviated as mm²) is a unit of area in the International System of Units (SI). It represents a square with sides that each measure 1 millimeter (mm) in length.
One square millimeter is equal to 0.000001 square meters (m²) because there are 1,000 millimeters in a meter, and when you square that length, you get 0.001 square meters. Alternatively, you can express it as 1 square meter being equal to 1,000,000 square millimeters.
To visualize the size of a square millimeter, you can think of an extremely small square with sides that are each 1 millimeter long. It is a minuscule unit of area and is often used for measuring very tiny objects or areas, especially in scientific and engineering applications where precision is crucial.
The "square foot (US survey)" is a unit of area used in the United States primarily for land surveying and mapping purposes. It differs from the standard square foot because it is based on the U.S. survey foot, which is a historical unit of length used in land surveying in the United States. The U.S. survey foot is slightly different from the international foot.
One square foot (US survey) is equal to approximately 0.0929034119223 square meters (m²) or about 0.111111 square yards (yd²).
This unit is used in various land-related applications, particularly in the United States, where the U.S. survey foot and the square foot (US survey) are still employed for legal and historical reasons in certain land surveys and property descriptions. It's essential to be aware of the specific units being used when dealing with land measurements to avoid any discrepancies or errors.