BMW 8 Series (G14) (2018) is 433 mm (17.05 inch) longer and 68 mm (2.68 inch) wider than Mercedes GLA-Class (2020).
Mercedes GLA-Class (2020) is 272 mm (10.71 inch) higher, 360 kg (794 lbs) lighter and has 85 liters (3.00 ft3) bigger cargo space than BMW 8 Series (G14) (2018).