We use the AdS/CFT correspondence to compute the central charges of the d = 4, N = 2 superconformal field theories arising from N D3-branes at singularities in F-theory. These include the conformal theories with E_n global symmetries. We compute the central charges a and c related to the conformal anomaly, and also the central charges k associated to the global symmetry in these theories. All of these are related to the coefficients of Chern-Simons terms in the dual string theory on AdS₅. Our computation is exact for all values of N, enabling several tests of the dualities recently proposed by Argyres and Seiberg for the E₆ and E₇ theories with N = 1.