  A measurement of the invisible width of the $Z$ boson using events with jets
and missing transverse momentum is presented using 37 $\mbox{fb\(^{-1}\)}$ of
13 TeV proton-proton data collected by the ATLAS detector in 2015 and 2016. The
ratio of $Z\rightarrow \textrm{inv}$ to $Z\rightarrow\ell\ell$ events, where
inv refers to non-detected particles and $\ell$ is either an electron or a
muon, is measured and corrected for detector effects. Events with at least one
energetic central jet with $p_{\textrm{T}} \geq 110$ GeV are selected for both
the $Z\rightarrow \textrm{inv}$ and $Z\rightarrow\ell\ell$ final states to
obtain a similar phase space in the ratio. The invisible width is measured to
be $506\pm2 \textrm{ (stat.)} \pm12 \textrm{ (syst.)}$ MeV and is the single
most precise recoil-based measurement. The result is in agreement with the most
precise determination from LEP and the Standard Model prediction based on three
neutrino generations.
