The flag of the Cocos (Keeling) Islands has an aspect ratio of 1:2. It consists of three horizontal stripes with the following color codes and proportions:

1. Top stripe: Green (#009966), occupying 1/3 of the flag's height.
2. Middle stripe: White (#FFFFFF), occupying 1/3 of the flag's height.
3. Bottom stripe: Blue (#003399), occupying 1/3 of the flag's height.

On the left side of the white stripe, there is a yellow crescent moon (#FFCC00) and a yellow twelve-pointed star (#FFCC00). The crescent moon is vertically centered on the white stripe, while the star is placed above the crescent moon, with one point touching the top edge of the white stripe. The star's diameter is equal to half the height of the white stripe, and the distance between the star and the crescent moon is equal to 1/24 of the flag's height.