A measurement of inclusive differential multijet cross sections and ratios is presented. The analysis is based on data from proton-proton (pp) collisions collected by the CMS [1] experiment at a center-of-mass energy of \(\sqrt{s}=13\) TeV, corresponding to an integrated luminosity of 59.82 \({\,\text {fb}^{-1}} \) collected during the LHC Run2. The ratios from the corresponding differential multijet cross sections with different multiplicities \({R_{\text {mn}}}\) are also calculated, where m, n stand for the multiplicity of the numerator and denominator. Jets are reconstructed using the anti- \(k_{\text {T}}\) clustering algorithm with a jet cone size of \(R=0.8\) . The analysis considers events with jets with transverse momentum \(p_{\text {T}} >150 \text {GeV}\) and absolute rapidity within \(|y|<2.5\) . The inclusive differential multijet cross sections and their ratios \(R_{\text {32}} \) , \(R_{\text {43}} \) , and \(R_{\text {42}} \) are measured as a function of the average transverse momentum of the two leading jets. Experimental data are compared to predictions from simulations using various Monte Carlo event generators.