In the oil and gas industry, drilling mud plays a vital role in the drilling process. This study aims to analyze the filtration rate of water-based mud with silicon dioxide and zinc oxide nanoparticles. In addition, different concentrations of high-temperature starch with both silica and zinc oxide nanoparticles were also investigated. It further compares the effects of various sized and concentrated silicon dioxide and zinc oxide nanoparticles, emphasizing how well water-based drilling muds filter water and function in well simulation scenarios. Filtration properties were determined using high pressure and high temperature (HPHT) and American Petroleum Institute (API) filter presses. The results showed that nanoparticles provide better filtration rate performance. Notably, zinc oxide and silicon dioxide nanoparticles reduced the HPHT filtration rate of conventional water-based mud by 26.2% and 52.3%, respectively.