It has a 3:2 ratio between length and width, it is divided horizontally into two bands of equal size (being the lower red). The upper area is divided once: in a square (blue), with a single centered white star; and rectangle (white), whose lengths are in proportion 1:2.
The star may represent a guide to progress and honor while other interpretations refer to its reference to an independent state; blue symbolizes the sky and the Pacific Ocean, white is for the snow-covered Andes, and red stands for the blood spilled to achieve independence.
According to the epic poem La Araucana, the colors were derived from those from the flag flown by the Mapuche during the Arauco War. "Flag Day" is held each year on the ninth of July to commemorate the 77 soldiers who died in the 1882 Battle of La Concepción.