This article is about the number. For the pop music album, see The Golden Ratio (album). For calendar dates, see Golden number (time).
In mathematics and the arts, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to their maximum. The figure on the right illustrates the geometric relationship. Expressed algebraically, for quantities a and b witha > b,
where the Greek letter phi () represents the golden ratio. Its value is: