Golden Ratio Calculator

In short The golden ratio is 1.618, the number where the whole divided by the larger part equals the larger part divided by the smaller. As a layout tool it is genuinely useful: split 1000px by it and you get 618 and 382, which is a more interesting division than a half and a more balanced one than a third. It works well for a content column against a sidebar, for the relationship between a heading and its body text, and for cropping an image to proportions that feel settled rather than arbitrary. What it is not is a law of beauty. The claims usually attached to it — that the Parthenon, the Mona Lisa and the nautilus shell are built on it — are mostly retrofitted, and the measurements only work if you choose where to put the lines. A nautilus shell is a logarithmic spiral with a ratio nowhere near 1.618. Treat 1.618 as one useful proportion among several: 3:2, 4:3 and the musical ratios are equally pleasant and often more practical, because they divide into whole pixels. Use it when it helps you decide, and do not let it override a layout that already works.