Kia Optima (2015) is 445 mm (17.52 inch) longer, 26 mm (1.02 inch) wider, 18 kg (40 lbs) lighter and has 75 liters (2.65 ft3) bigger cargo space than Mercedes GLA-Class (2017).
Mercedes GLA-Class (2017) is 146 mm (5.75 inch) higher than Kia Optima (2015).