The golden ratio is a special proportion in which a line is divided so that the smaller part is to the larger part as the larger part is to the whole. That ratio is about 1 to 1.618. It has long been felt to be especially harmonious and is therefore often applied in architecture, art and design.
The proportion
The golden ratio is denoted by the Greek letter phi (φ). If you divide a line into a large part (a) and a small part (b), the golden ratio holds when:
- a + b is to a as a is to b
- the value of φ is about 1.618
This proportion is linked to the Fibonacci sequence (1, 1, 2, 3, 5, 8, 13, 21…), in which the ratio of successive numbers comes ever closer to φ.
Application in building and design
The golden ratio is used as a tool to set pleasing, balanced proportions:
- Facade layout — the ratio of height to width, or of window areas to wall areas
- Floor plans — the ratio of length to width of a room
- Detailing — the placing of divisions, mouldings and accents
- Graphic design — the layout of pages, logos and compositions
It is important to note that the golden ratio is not a law but a guideline: many classical buildings approach the proportion, but not always exactly. As a design aid, it helps a composition look calm and balanced.
Related terms
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