Cadillac STS (2018) is 674 mm (26.54 inch) longer, 54 mm (2.13 inch) wider, 20 mm (0.79 inch) higher and has 47 liters (1.66 ft3) bigger cargo space than Mercedes A-Class (2015).
Mercedes A-Class (2015) is 364 kg (802 lbs) lighter than Cadillac STS (2018).