 This study evaluates 22 grid precipitation data sets for the period 2000-2016 using daily gauge observations from 76,086 gauges worldwide and hydrological modeling to calibrate the HBV conceptual model against streamflow records. The results show marked differences in spatial temporal patterns and accuracy among the data sets. Among the uncorrected P data sets, satellite and re-analysis-based MSWEPing version 1.2 and version 2.0 generally showed the best temporal correlations with gauge observations followed by re-analysis in satellite and re-analysis-based chirp version 2.0. Among the corrected P data sets, those directly incorporating daily gauge data generally provided the best calibration scores. The study highlights large differences in estimation accuracy and emphasizes the importance of P data set selection in both research and operational applications. This article was authored by H. E. Beck and Virgopalan, M. Pan, and others. We are article.tv, links in the description below.