School starting age, primary school - country data from around the world:
The average for 2014 was 6.07 years.
The highest value was in El Salvador: 7 years and the lowest value was in Ireland: 5 years.
Below is a chart for all countries where data are available for: School starting age, primary school.
World bank definition: Entrance age of primary is the age at which students would enter primary education, assuming they had started at the official entrance age for the lowest level of education, had studied full-time throughout and had progressed through the system without repeating or skipping a grade.