A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton–proton collisions at s√=13TeV . The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9 fb−1 . The measurement is performed for the ℓν jj final state (with ℓν indicating a lepton–neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass mjj>120GeV and transverse momenta pTj>25GeV . The cross section of the process is measured in the electron and muon channels yielding σEW(Wjj)=6.23±0.12(stat)±0.61(syst)pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are −2.3<cWWW/Λ2<2.5TeV−2 , −8.8<cW/Λ2<16TeV−2 , and −45<cB/Λ2<46TeV−2 . These results are combined with the CMS EW Zjj analysis, yielding the constraint on the cWWW coupling: −1.8<cWWW/Λ2<2.0TeV−2 .