This article presents a dataset of mesiodistal and buccolingual crown measurements from 712 deciduous incisors, canines, and molars belonging to 52 Spanish children from the Ratón Pérez Collection. This collection housed at the National Research Center on Human Evolution (CENIEH, for its acronym in Spanish) in Burgos, Spain, constitutes one of the most valuable citizen science initiatives on the international stage. The dataset offered in this article is unusual and especially valuable because it belongs to individuals who have donated at least ten associated teeth over the years. Measurements were obtained following standardized odontometric protocols to ensure accuracy and comparability. Unlike other studies, here we provide all individual measurements, making it the first openly available reference collection of raw deciduous tooth metrics derived from a well-documented and ethically-sourced sample. These data enable exploration of variability in primary tooth size, facilitate comparisons with other populations, and support studies on growth, development, and child forensic identification. By making this original dataset publicly available, we contribute a valuable tool for multiple scientific disciplines such as pediatric dentistry, forensic sciences, bioarchaeology, dental anthropology or human evolution among other disciplines.