The flag of Gibraltar has an aspect ratio of 1:2. It consists of two horizontal stripes, with the top stripe being white and occupying 2/3 of the flag's height, and the bottom stripe being red and occupying 1/3 of the flag's height. The color codes for the flag are:

• White: #FFFFFF
• Red: #CE1126

On the upper hoist-side (left) of the white stripe, there is a three-towered red castle with a gold key hanging from the center tower by a chain. The castle and key have specific geometric properties:

• Castle width: 1/3 of the flag's length
• Castle height: 1/3 of the flag's height
• Key length: 1/4 of the flag's length
• Key width: 1/20 of the flag's height

The color codes for the castle and key are:

• Red (castle): #CE1126
• Gold (key): #D3AB3A