Abstract: No known single-stage dry low emissions fuel injectors are capable of effectively operating over all ranges of hydrogen concentrations in hydrogen/natural gas fuel mixtures. Accordingly, a fuel injector is disclosed that is capable of operating in both a premix mode for fuel mixtures with lower hydrogen concentrations and a micromix mode for fuel mixtures with higher hydrogen concentrations. The fuel injector may comprise premix jets near an inlet of the fuel injector, optionally within one or more swirlers, and micromix jets near the outlet of the fuel injector. In the premix mode, fuel with lower hydrogen concentrations is provided to the premix jets, whereas in the micromix mode, fuel with higher hydrogen concentrations is provided to the micromix jets.