The trace is a decategorification functor which can often reveal additional structure not visible in the Grothendieck group. For instance, the categories of modules over the cyclotomic KLR algebra associated to a Lie algebra $\mathfrak{g}$ of type ADE have Grothendieck groups isomorphic to highest weight integrable representations of the quantum group $U_q(\mathfrak{g})$, while their traces are isomorphic to Weyl modules over the current algebra of $\mathfrak{g}$. Webster introduced a generalization of cyclotomic KLR algebras called tensor product algebras. Modules over the these algebras categorify tensor products of highest weight integrable modules of $U_q(\mathfrak{g})$. In this talk, we investigate the trace of Webster's tensor product categorification, and show that it is isomorphic to a tensor product of Weyl modules. This is joint work with Christopher Leonard (Virginia).