McLaren 720S (2020) is 150 mm (5.91 inch) longer and 273 mm (10.75 inch) wider than Mercedes B-Class (2018).
Mercedes B-Class (2018) is 361 mm (14.21 inch) higher, 72 kg (159 lbs) lighter and has 283 liters (9.99 ft3) bigger cargo space than McLaren 720S (2020).