BMW 8 Series (G15) (2018) is 43 mm (1.69 inch) wider than Citroen C6 (2017).
Citroen C6 (2017) is 67 mm (2.64 inch) longer, 122 mm (4.80 inch) higher, 108 kg (238 lbs) lighter and has 1 liters (0.04 ft3) bigger cargo space than BMW 8 Series (G15) (2018).