Provided is a tempered glass, which has a compressive stress layer on a surface thereof, comprising, in terms of mol %, 40 to 80% of SiO2, 5 to 15% of Al2O3, 0 to 8% of B2O3, 0 to 10% of Li2O, 5 to 20% of Na2O, 0.5 to 20% of K2O, 0 to 10% of MgO, and 8 to 16.5% of Al2O3+MgO, wherein the glass has, in terms of a molar ratio, a (Li2O+Na2O+K2O)/Al2O3 ratio of 1.4 to 3, an Na2O/Al2O3 ratio of 1 to 3, and an MgO/Al2O3 ratio of 0 to 1, and is substantially free of As2O3, PbO, and F.