Comparative studies of surface processes across planetary bodies are hindered by the lack of consistently parameterized, openly accessible soil data, especially the grain-size distribution (GSD) data. Here we present PlanetGSD 1.0, the first standardized and unified cross-planetary GSD database. It comprises 6,527 measurements from Earth (4,419 samples, 20 geomorphic settings), the Moon (379 samples, 8 missions), and Mars (1,729 rover-derived estimates, 4 landing areas), covering seven orders of magnitude in grain size (0.0001 &ndash; 600 mm). The traditional textural fractions have been transferred into a unique parameter set (<em>&mu;</em>, <em>D_c</em>, <em>n</em>) derived from the unified GSD (UGSD) function (median <em>R</em>² = 0.988), with quality metrics, georeferenced metadata, site-level Weibull statistics, and open-source analysis codes. Technical validation confirms high fitting quality across all samples (97.8 % with <em>R</em>² &gt; 0.95) and robust inter-operator reproducibility for Martian image-derived measurements (coefficient of variation &lt; 8.3 % for key parameters). The complete dataset is openly available on Figshare (Zhang, 2026) under CC BY 4.0 license. PlanetGSD 1.0 enables robust cross-planetary comparison of regolith properties, benchmarking of simulants, and data-driven landing site assessment, establishing a foundational resource for planetary science.