BMW 8 Series (G15) (2018) is 568 mm (22.36 inch) longer and 134 mm (5.28 inch) wider than Mazda 6 Atenza (2015).
Mazda 6 Atenza (2015) is 201 mm (7.91 inch) higher, 650 kg (1,433 lbs) lighter and has 87 liters (3.07 ft3) bigger cargo space than BMW 8 Series (G15) (2018).