We investigate whether the hypercharge assignments in the standard model can be interpreted as a hint at grand unification in the context of heterotic string theory. Our analysis is a follow-up to the recent mini-landscape analysis of the ${\mathbb{Z}}_6$-II orbifold of the ${\mathrm{E}}_8\times {\mathrm{E}}_8^{\prime }$ heterotic string. In that analysis, an intermediate grand unified theory (GUT) was a requirement for finding MSSM-like theories. Nevertheless, about 1% of the models in this mini-landscape were MSSM-like. In this paper we remove this GUT restriction. To this end, we introduce a general method to calculate $\mathrm{U}(1{)}_Y$ for any heterotic orbifold and compare our findings to the cases where hypercharge arises from a GUT. Surprisingly, in the overwhelming majority of 3-2 standard models, a nonanomalous hypercharge direction can be defined, for which the spectrum is vectorlike. For these models, we calculate ${sin}^2{\theta }_w$ to see how well it agrees with the standard GUT value. We find that 12% have ${sin}^2{\theta }_w=3/8$, while all others have values which are less. Finally, 89% of the models with ${sin}^2{\theta }_w=3/8$ have $\mathrm{U}(1{)}_Y\subset \mathrm{SU}(5)$.

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