Method for determining the values of a set of n optical parameters (P1, P2, . . . , Pn) of an ophthalmic lens, n being an integer greater than or equal to 1, the method comprising: an nominal ophthalmic lens data providing step, an ophthalmic lens providing step, an optical surface measuring step, a surface errors determining step during which a set of m surface error parameters (α1, α2, . . . , αm) is determined, m being an integer greater than or equal to 1, an optical parameter determining step during which each optical parameter of the set of optical parameters is determined by: P i = P i , 0 + [ ∑ j = 1 m ⁢ ⁢ ( ∂ P i ∂ α j ) 0 × Δα j ] + A i with Pi the value of the ith optical parameter of the manufactured optical lens, Pi,0 the value of the ith optical parameter of the nominal optical lens, ( ∂ P i ∂ α j ) 0 the value of the derivative of Pi with respect to the jth surface error parameter αj on the nominal surface and Δαj the value of the jth surface error parameter, and Ai a combination of terms of order greater or equal to 2 for each Pi.