Abstract. Known classification results allow us to find the number of (equivalence classes of) fine gradings on matrix algebras and on classical simple Lie algebras over an algebraically closed field F (assuming char F = 2 in the Lie case). The computation is easy for matrix algebras and especially for simple Lie algebras of type Br (the answer is just r + 1), but involves counting orbits of certain finite groups in the case of Series A, C and D. For X ∈ {A, C, D}, we determine the exact number of fine gradings, N X (r), on the simple Lie algebras of type Xr with r ≤ 100 as well as the asymptotic behaviour of the average,N X (r), for large r. In particular, we prove that there exist positive constants b and c such that exp(br 2/3 ) ≤N X (r) ≤ exp(cr 2/3 ). The analogous average for matrix algebras Mn(F) is proved to be a ln n + O(1) where a is an explicit constant depending on char F.