What aspect ratio yields minimal area for a standard‐cell integrated circuit (IC) that has a fixed number of cells and set of interconnections? Do square ICs really have minimal area? Our deterministic mathematical model provides answers and can help IC designers who want to vary the aspect ratio of a standard‐cell block incorporated in a custom IC. Through a series of layout experiments, we show the model to be very accurate (the average error is 2.0 percent). We show that a cubic equation must be solved to find the aspect ratio that yields the theoretical minimal area. Key ingredients in our analysis are the maximum vertical and horizontal densities, which we empirically show to be linear functions of the number of rows. The major conclusion of this work is that square ICs do yield minimal area. But even over a wide range of aspect ratios (i.e., nonsquare shapes), little increase in area is incurred.