<jats:title>Abstract</jats:title><jats:p>Energy transfers by internal gravity wave–wave interactions in spectral space are diagnosed from numerical model simulations initialized with realizations of the Garrett–Munk spectrum in physical space and compared with the predictions of the so-called scattering integral or kinetic equation. Averaging the random phase of the initialization, the energy transfers by wave–wave interactions in the model agree well with the predictions of the kinetic equation for certain ranges of frequency and wavenumbers. This validation allows now, in principle, the use of the energy transfers predicted by the kinetic equation to design a global spectral energy budget for internal gravity waves in the ocean where divergences of energy transports in physical and spectral space balance forcing, dissipation, the energy transfers by the wave–wave interactions, or the rate of change of the spectral wave energy. First global estimates show indeed accumulation of the wave energy in a range of latitude <jats:italic>ϕ</jats:italic> consistent with tidal waves at frequency <jats:italic>ω</jats:italic><jats:sub><jats:italic>T</jats:italic></jats:sub> propagating toward the latitudinal window where 2 &lt; <jats:italic>ω</jats:italic><jats:sub><jats:italic>T</jats:italic></jats:sub>/<jats:italic>f</jats:italic>(<jats:italic>ϕ</jats:italic>) &lt; 3, as predicted by the kinetic equation.</jats:p>