Abstract A measurement is presented of electroweak (EW) production of a $$\mathrm{W} $$ W boson in association with two jets in proton–proton collisions at $$\sqrt{s}=13\,\text {Te}\text {V} $$ s=13Te . The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9$$\,\text {fb}^{-1}$$ fb-1 . The measurement is performed for the $$\ell \nu $$ ℓν jj final state (with $$\ell \nu $$ ℓν indicating a lepton–neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass $$m_\mathrm {jj} >120\,\text {Ge}\text {V} $$ mjj>120Ge and transverse momenta $$p_\mathrm {T j} > 25\,\text {Ge}\text {V} $$ pTj>25Ge . The cross section of the process is measured in the electron and muon channels yielding $$\sigma _\mathrm {EW}(\mathrm{W} \mathrm {jj})= 6.23 \pm 0.12 \,\text {(stat)} \pm 0.61 \,\text {(syst)} \,\text {pb} $$ 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 $$-2.3< c_{{\mathrm{W} \mathrm{W} \mathrm{W}}}/\varLambda ^2 < 2.5\,\text {Te}\text {V} ^{-2}$$ -2.3<cWWW/Λ2<2.5Te-2 , $$-8.8< c_{\mathrm{W}}/\varLambda ^2 < 16\,\text {Te}\text {V} ^{-2}$$ -8.8<cW/Λ2<16Te-2 , and $$-45< c_{\mathrm{B}}/\varLambda ^2 < 46\,\text {Te}\text {V} ^{-2}$$ -45<cB/Λ2<46Te-2 . These results are combined with the CMS EW $$\mathrm{Zjj} $$ Zjj analysis, yielding the constraint on the $$c_{{\mathrm{W} \mathrm{W} \mathrm{W}}}$$ cWWW coupling: $$-1.8< c_{{\mathrm{W} \mathrm{W} \mathrm{W}}}/\varLambda ^2 < 2.0\,\text {Te}\text {V} ^{-2}$$ -1.8<cWWW/Λ2<2.0Te-2 .