The absolute configuration of (R)-(+)-camphor-derived furyl hydroperoxide and alcohol, which exhibit a number of stable conformations, has been successfully accomplished on the basis of time dependent density functional response theory (TDDFT) calculations of optical rotation. Assuming standard approximations, it has been found that the results are improved by using populations for the conformers derived from free energy differences instead of the commonly used PES minimum differences. This represents the first computational study devoted to the direct determination of absolute configuration of an optically pure hydroperoxide, without any need of its further chemical derivatization.