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We obtain an a-priori $$W_{{\mathrm{loc}}}^{1,\infty }\left( \Omega ; {\mathbb {R}}^{m}\right) $$-bound for weak solutions to the elliptic system $$\begin{aligned} \text {div}A\left( x,Du\right) =\sum _{i=1}^{n}\frac{\partial }{\partial x_{i}} a_{i}^{\alpha }\left( x,Du\right) =0,\;\;\;\;\;\alpha =1,2,\ldots ,m, \end{aligned}$$where $$\Omega $$ is an open set of $${\mathbb {R}}^{n}$$, $$n\ge 2$$, u is a vector-valued map $$u:\Omega \subset {\mathbb {R}}^{n}\rightarrow {\mathbb {R}}^{m}$$ . The vector field $$A\left( x,\xi \right) $$ has a variational nature in the sense that $$A\left( x,\xi \right) =D_{\xi }f\left( x,\xi \right) $$, where $$ f=f\left( x,\xi \right) $$ is a convex function with respect to $$\xi \in {\mathbb {R}}^{m\times n}$$. In this context of vector-valued maps and systems, a classical assumption finalized to the everywhere regularity is a modulus-dependence in the energy integrand; i.e., we require that $$f\left( x,\xi \right) =g\left( x,\left| \xi \right| \right) $$, where $$ g\left( x,t\right) $$ is convex and increasing with respect to the gradient variable $$t\in \left[ 0,\infty \right) $$. We allow x-dependence, which turns out to be a relevant difference with respect to the autonomous case and not only a technical perturbation. Our assumptions allow us to consider both fast and slow growth. We consider fast growth even of  exponential type; and slow growth, for instance of Orlicz-type with energy-integrands such as $$g\left( x,\left| Du\right| \right) =a(x)|Du|^{p(x)}\log (1+|Du|)$$ or, when $$n=2,3$$, even asymptotic linear growth with energy integrals of the type $$\begin{aligned} \int _{\Omega }g\left( x,\left| Du\right| \right) dx\,=\int _{\Omega }\left\{ \left| Du\right| -a\left( x\right) \sqrt{\left| Du\right| }\right\} dx. \end{aligned}$$

A-priori gradient bound for elliptic systems under either slow or fast growth conditions