The Hong Kong Early Child Development Scale (HKECDS) is a tool for assessing holistic early child development in preschoolers aged from three to six years. The original version of the scale, HKECDS, was updated in 2019 (HKECDS-2) to reflect the contemporary context and local curricular expectations. Children (n = 144) from three kindergartens in Hong Kong completed the HKECDS-2 in individual sessions. Rasch model analysis and expert discussions resulted in a short version of the scale (HKECDS-3) with 50 items in nine domains. The domains are Personal and self-care (4 items), Language development (7 items), Pre-academic learning (10 items), Cognitive development (6 items), Gross motor (4 items), Fine motor (2 items), Health and safety (5 items), Moral development (6 items), and Society and environment (6 items). There were significant correlations between findings from the updated version of the tool, HKECDS-3 and the HKECDS-2 (long form), and older children had significantly higher scores than younger children.