BMW 8 Series (G15) (2018) is 404 mm (15.91 inch) longer and 81 mm (3.19 inch) wider than BMW X1 (2018).
BMW X1 (2018) is 257 mm (10.12 inch) higher, 454 kg (1,001 lbs) lighter and has 85 liters (3.00 ft3) bigger cargo space than BMW 8 Series (G15) (2018).