The physical and psychological readiness of children will affect the transition phase of children entering more formal education. Increasing children's' school readiness is one the most important aims of quality early childhood education. This research aims to explore the experiences of early childhood educators in assessing the level of readiness of children entering primary education. This research is qualitative research using a phenomenological approach. Data was collected through focus group discussions (FGDs) involving 20 early childhood educators who covered kindergarten, RA, and PAUD in Cilacap, Central Java, Indonesia. The data analysis technique was carried out by applying the Miles and Huberman model. The results showed the concept of school readiness has been widely recognized by early childhood educators and colored the process of early childhood learning. Educators' perceptions of the dimensions of school readiness are based on the achievements of children's development, which include moral and religious values, physical-motor, cognitive, language, social-emotional, and art. The assessment of the child's developmental achievements is carried out formative with most using performance assessments. The plural assessment rubric is used as an observation instrument for the child's performance.