Sound assessment tools are needed to evaluate effects of mathematics interventions that familiarize children with early mathematics concepts before they enter the formal school system. We developed a short version of an existing early mathematics tool based on analyses of data collected in a nationally representative Danish sample. Research findings: The Danish adaptation and development process of the Tools for Early Assessment in Math (TEAM) for children aged 3-6 years was carried out in four steps: (a) choosing and translating relevant items, (b) conducting a pilot study, (c) testing items in a representative sample of Danish children aged 3-6 years (n = 5,621), and (d) analyses based on Rasch models. The process resulted in a final 19-item version–the DK-TEAM (final)–that has no differential item functioning relative to age and gender and is sensitive to the full range of abilities. The great majority of the children viewed the test as enjoyable. Practice or Policy: The DK-TEAM (final) appears to be broadly applicable for young Danish children, though the modest reliability at 3 years (which may be remediable by adding easy items) should be kept in mind.