Mazda 6 (2020) is 197 mm (7.76 inch) longer and 25 mm (0.98 inch) wider than Opel Astra Sports Tourer (2014).
Opel Astra Sports Tourer (2014) is 85 mm (3.35 inch) higher, 84 kg (185 lbs) lighter and has 60 liters (2.12 ft3) bigger cargo space than Mazda 6 (2020).
