Mercedes CLA-Class (2017) is 252 mm (9.92 inch) longer, 145 mm (5.71 inch) higher and has 308 liters (10.88 ft3) bigger cargo space than Porsche Cayman (2018).
Porsche Cayman (2018) is 22 mm (0.87 inch) wider and 80 kg (176 lbs) lighter than Mercedes CLA-Class (2017).