Systems, devices, and methods for expanding the eyebox of a wearable heads-up display are described. A light guide with an expanded eyebox includes a light guide material, an in-coupler, an outcoupler, and a gradient refractive index (GRIN) material. The in-coupler and the out-coupler may comprise a GRIN material. An eyeglass lens with expanded eyebox includes a light guide with expanded eyebox. A wearable heads-up display includes an eyeglass lens including a light guide with an expanded eyebox.