We consider the ratio of cross sections of double-to-single Higgs boson production at the Large Hadron Collider at 14 TeV. Since both processes possess similar higherorder corrections, leading to a cancellation of uncertainties in the ratio, this observable is well-suited to constrain the trilinear Higgs boson self-coupling. We consider the scale variation, parton density function uncertainties and conservative estimates of experimental uncertainties, applied to the viable decay channels, to construct expected exclusion regions. We show that the trilinear self-coupling can be constrained to be positive with a 600 fb-1 LHC dataset at 95% confidence level. Moreover, we demonstrate that we expect to obtain a ~ +30% and ~ -20% uncertainty on the self-coupling at 3000fb-1 without statistical fitting of differential distributions. The present article outlines the most precise method of determination of the Higgs trilinear coupling to date.