Mercedes B-Class (2017) is 287 mm (11.30 inch) higher, 56 kg (123 lbs) lighter and has 302 liters (10.66 ft3) bigger cargo space than Porsche 718 Cayman (2020).
Porsche 718 Cayman (2020) is 65 mm (2.56 inch) longer and 17 mm (0.67 inch) wider than Mercedes B-Class (2017).