Mercedes GLB-Class (2019) is 256 mm (10.08 inch) longer, 34 mm (1.34 inch) wider, 366 mm (14.41 inch) higher and has 408 liters (14.41 ft3) bigger cargo space than Porsche Cayman (2020).
Porsche Cayman (2020) is 40 kg (88 lbs) lighter than Mercedes GLB-Class (2019).