Mercedes B-Class (2014) is 1 mm (0.04 inch) longer, 262 mm (10.31 inch) higher, 46 kg (101 lbs) lighter and has 336 liters (11.87 ft3) bigger cargo space than Porsche 718 Cayman (2017).
Porsche 718 Cayman (2017) is 15 mm (0.59 inch) wider than Mercedes B-Class (2014).