Thin films formed under high acceleration fields in a spinning disk reactor (SDR) are characterized by high shear rates and intense surface ripples which are known to play an important role in improving the selectivity, yield, and final product quality in many mixing-dependent processes. The micromixing efficiency of a small-scale SDR of 10?cm disk diameter for a range of hydrodynamic conditions by means of the iodide-iodate test reaction is determined. Under optimized conditions, the SDR exhibits a better micromixing performance than the mechanically stirred vessel and other continuous intensified reactors, such as the rotating packed bed, when processing water-like fluids at the highest investigated flow rate of 5?mL?s1. These results highlight the potential of the SDR as an alternative intensified mixer/reactor for processes where a high degree of mixing is desirable.