BMW 8 Series (G14) (2018) is 63 mm (2.48 inch) wider than Mazda 6 (2020).
Mazda 6 (2020) is 52 mm (2.05 inch) longer, 111 mm (4.37 inch) higher, 364 kg (802 lbs) lighter and has 130 liters (4.59 ft3) bigger cargo space than BMW 8 Series (G14) (2018).