The Golden Ratio, an irrational mathematical constant that signifies when two quantities are in the ratio “if the ratio of the sum of the quantities to the larger quantity is equal to the ratio of the larger quantity to the smaller one,” was the basis for Twitter’s new design.
Twitter’s Creative Direction Doug Bowman explains:
“To anyone curious about #NewTwitter proportions, know that we didn’t leave those ratios to chance.
This, of course, only applies to the narrowest version of the UI. If your browser window is wider, your details pane will expand to provide greater utility, throwing off these proportions. But the narrowest width shows where we started, ratio-wise.”
As Twitter user Neven Mrgan explained, the Golden Ratio can be found in the most unlikely of places: