Buick Regal (2014) is 453 mm (17.83 inch) longer, 191 mm (7.52 inch) higher and has 217 liters (7.66 ft3) bigger cargo space than Toyota GR Supra (2018).
Toyota GR Supra (2018) is 3 mm (0.12 inch) wider and 36 kg (79 lbs) lighter than Buick Regal (2014).