The flag of Puerto Rico consists of five alternating horizontal stripes of equal width and color, with a blue triangle on the left side that extends to the middle of the flag's height. The three points of the triangle represent the three branches of the government, while the blue color stands for the sky and coastal waters.

The specific colors used in the flag are defined by law as follows:

• Red: Pantone 186C / RGB 255, 0, 0
• White: Pantone Safe / RGB 255, 255, 255
• Blue: Pantone 286C / RGB 0, 50, 143

The aspect ratio of the flag is 2:3, and its geometric properties are fairly simple - rectangular shape with straight edges. The flag measures approximately 90 cm x 135 cm (3 ft x 4.5 ft) in size when used ceremonially, although there are variations in size for different uses.