Mercedes B-Class (2020) is 40 mm (1.57 inch) longer, 267 mm (10.51 inch) higher and has 255 liters (9.01 ft3) bigger cargo space than Porsche 718 Cayman (2014).
Porsche 718 Cayman (2014) is 4 mm (0.16 inch) wider and 184 kg (406 lbs) lighter than Mercedes B-Class (2020).