Everything you need to know about your pizza.
Pizza area = π × (diameter/2)². A 14-inch pizza has 153.9 square inches — each of 8 slices is 19.2 sq in. At roughly 2.5 calories per square inch (cheese pizza), that's about 48 calories per square inch of slice, or ~240 calories per large slice. The cost per square inch reveals the true value: a $15 large pizza (14-inch) costs $0.097/sq in, while a $10 medium (12-inch) costs $0.088/sq in — making the medium the slightly better value in this case. Always do the math before ordering! Fun fact: Americans eat approximately 3 billion pizzas per year (23 pounds per person), making pizza a $46 billion industry in the US alone.