BMW 8 Series (G15) (2018) is 63 mm (2.48 inch) wider than Mazda 6 (2016).
Mazda 6 (2016) is 21 mm (0.83 inch) longer, 109 mm (4.29 inch) higher, 454 kg (1,001 lbs) lighter and has 60 liters (2.12 ft3) bigger cargo space than BMW 8 Series (G15) (2018).