Nucl. Part. Phys. Proc. Nucl. Part. Phys. Proc. Jet production and $\alpha_{s}$ measurements at CMS Flouris Giannis Ioannina U. 2016 270-272 8 12 The measurements of inclusive jet, dijet and trijet cross sections, of the dijet azimuthal decorrelations, the ratio of the inclusive 3-jet to 2-jet cross sections are presented. The measurements use the samples of proton-proton collisions collected with the CMS detector at the LHC at a center-of-mass energy of 7 and 8 TeV. research-article