A round bar is a cylindrical metal rod that has a circular cross-section. It is widely utilized in various sectors, including building, manufacturing, and engineering. Round bars come in various materials, including steel, aluminum, and brass, each with qualities and applications. They are available in various diameters and lengths to satisfy specific requirements in structural support, mechanical components, shafts, fasteners, and other applications.

Round bars are generally measured by their diameter, the distance between the bar's center and the widest point. The diameter is usually measured in inches or millimeters.Measure the diameter of a round bar correctly using a calliper, micrometer, or ruler. Measure across the center of the bar for an accurate reading.

A round bar's thickness is determined by its diameter. It is the distance between one side of a circular cross-section and the other, passing through the center. The thickness of a round bar varies according to its intended purpose and the requirements specified by the manufacturer or supplier.