The Golden Ratio in Architecture

The golden ratio is a special number, about 1.618. When a rectangle's sides follow this ratio, it looks especially pleasing to the eye. Architects have used it for thousands of years to design beautiful buildings.

What Is the Golden Ratio?

The golden ratio is found when you divide a line into two parts so that the longer part divided by the shorter part equals the whole line divided by the longer part. The answer is always about 1.618.

Rectangles with sides in this ratio are called golden rectangles. People find these shapes naturally beautiful and balanced.

Famous Buildings

The Parthenon in ancient Greece fits almost perfectly inside a golden rectangle. Many people believe its architects used the golden ratio on purpose to make it look harmonious.

Modern architects use the golden ratio too. The United Nations building in New York and parts of the Notre-Dame cathedral in Paris follow golden proportions. It is a math secret hidden in plain sight.

Fun Facts

• The golden ratio is represented by the Greek letter phi.
• Credit cards are very close to the shape of a golden rectangle.
• The ancient Egyptians may have used the golden ratio when building the pyramids.

Did You Know?

If you keep cutting a golden rectangle into a square and a smaller rectangle, the smaller rectangle is always another golden rectangle. This can go on forever!