The flag of Sri Lanka has an aspect ratio of 1:2. It consists of three main elements: a maroon rectangular field, a yellow border, and a green and orange vertical stripe on the left side.

1. Maroon field (Pantone 1955 C) - Rectangular shape, occupying most of the area of the flag.
2. Yellow border (Pantone 116 C) - Surrounds the entire flag, with a width equal to 1/32 of the flag's height.
3. Vertical stripes - On the left side, adjacent to the maroon field, there are two vertical stripes: a. Green stripe (Pantone 3415 C) - With a width equal to 1/16 of the flag's height. b. Orange stripe (Pantone 151 C) - With a width equal to 1/16 of the flag's height.

In the upper-left corner of the maroon field, there is a yellow-bordered dark red circle (Pantone 186 C) containing a golden lion holding a kastane sword in its right forepaw. The diameter of the circle is equal to 7/16 of the flag's height. Four stylized Bo leaves point inward from each cardinal direction around the circle, with their tips touching the circle's border.