1 An asphalt driveway typically costs about $2 -$5 a square foot, $1,200 - $3,000 for a 12'x50' single-car driveway; or $25,000 -$50,000 for up to a quarter mile. Some experts recommend sealing a driveway every year, depending on climate and other conditions. 2  Do-it-yourself supplies can cost $50 -$200 depending on the size and condition of the driveway, and the quality of the sealer. 3  Professional driveway sealing can cost $200 -$500 or more.