Convert Are (a) to Square Millimeter (mm²) instantly.
About these units
Are (a)
An are is a metric land unit equal to 100 m², originally invented during the development of the metric system but now largely overshadowed by the hectare (100 ares). Although rarely used independently in modern measurement, the are survives in real estate transactions in parts of Europe, where small land parcels—such as garden plots or rural homesteads—may be expressed in ares. It remains important historically, as it served as a transitional unit bridging the earliest metric innovations with modern large-scale land measurement practices.
Square Millimeter (mm²)
A square millimeter represents the area of a square measuring 1 millimeter on each side. It is a tiny unit used extensively in engineering, electronics, material science, and medical instrumentation. Mechanical designers use mm² to determine cross-sectional areas of wires, beams, micro-mechanical parts, and precision components. In electronics, PCB traces, microchips, and sensors often specify dimensions in mm² for clarity and precision. Biomedical sciences also use mm² for cell colony measurements, tissue sample surfaces, and microscopic fields of view. Its size makes it ideal for quantifying structures too small for cm² but too large for micrometer-scale units.