NONE 20260512111733367 wseas/wseas content-registration-form+ja@crossref.org content-registration-form WSEAS TRANSACTIONS ON MATHEMATICS 1109-2769 2224-2880 Nerisa Thornsri Department of Applied Statistics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok, THAILAND Sa-Aat Niwitpong Department of Applied Statistics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok, THAILAND Suparat Niwitpong Department of Applied Statistics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok, THAILAND The zero-inflated Rayleigh distribution combines zero values and a standard Rayleigh distribution that represents positive values. Percentiles are widely used tools for measuring data, particularly in skewed continuous datasets. This study aims to construct confidence intervals (CIs) for the percentile of the zero-inflated Rayleigh distribution. The proposed approaches include the generalized confidence interval (GCI), normal approximation (NA), and the percentile bootstrap confidence interval (PBCI). The zero-inflation probability is estimated using the variance-stabilizing transformation (VST), Wilson's Score, and Hannig’s methods. Their performances were evaluated using Monte Carlo simulations in R programming, comparing coverage probabilities (CPs) and average lengths (ALs). The results indicate that the GCI based on the VST outperformed the other methods. 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