Here, we present a new calibration technique that is faster than previous methods while maintaining the same level of accuracy. By employing stochastic optimisation and random speckle intensity patterns, we calibrate a digital twin that accurately models the experimental setup. Accurate calibration of the wavefront and intensity profile of the laser beam at the SLM display is key to the high fidelity of holographic potentials. By employing. The principles of phase-only SLM are introduced. Introduction Liquid Crystal Spatial Light Modulator (LC-SLM). Here, we introduce a simple and fast way to simultaneously extract these two types of SLM nonuniformities at single-pixel resolution using Twyman–Green interferometry without a piezoelectric transducer.