Research on toddlers' mathematical knowledge is sparse. Studies on children's mathematical competencies before school age have mostly focused on older children. Few of the previous studies have included large groups of toddlers, few have been conducted in natural settings, and few have been directed at a broad field of mathematical knowledge. The objective of this study was to investigate which mathematical competencies a large group of toddlers' in Norwegian kindergartens expressed through play and daily life activities. A total of 1,003 children participated. Their competencies were registered when they were between 30 and 33 months. The assessment material consisted of 36 items, divided into three main areas: number and counting, geometry and problem solving. The information was collected through authentic assessment; the staff in the kindergartens observed the toddlers' competencies in play and daily life activities. The competencies were registered as mastered, partly mastered or mastering not yet observed. The toddlers showed mathematical competencies in all areas observed. A wide dispersion was found; both for the total score and the subareas' scores. The largest variance was found in number and counting. Our participants displayed lower levels of competencies in using number words and reciting number sequences than reported from previous studies and higher competencies in puzzle-making and following instructions on spatial words. The results indicate that the assessment material may be a valuable tool for the preschool teachers in identifying the variety of competencies mastered by the children in kindergarten. The need for future research is highlighted and discussed.