A measurement of the $W$ and $Z$ bosons production differential cross section as a function of transverse momentum of weak vector bosons in $pp$ collisions at a centre-of-mass energy of 8 TeV. Both $W$ and $Z$ distributions are pre-FSR level and events are generated by Powheg. For the $Z$ boson analysis, the dimuon invariant mass selection, $60 < m < 120$ GeV.