What is a good student-teacher ratio?

National average is about 16:1. Ratios under 15:1 are considered favorable. Private schools often maintain 10-12:1.

Is ratio the same as class size?

No. Ratio includes all teachers (specialists, aides) divided among all students. Actual class sizes are often larger than the ratio suggests.

Research is mixed, but generally ratios under 15:1 correlate with better outcomes, especially in early grades.

Calculate the student-to-teacher ratio for a school or district to evaluate instructional capacity and compare institutions.

Total Students

Total Teachers (FTE)

Full-time equivalent teachers

Student-Teacher Ratio

16.7

Students per Teacher17

Teachers Needed for 15:134

Student-Teacher Ratio vs Total Students

The ratio divides total students by total full-time equivalent teachers.

Student-Teacher Ratio = Total Students / Total Teachers (FTE)

A ratio of 16:1 means 16 students for every teacher. This is different from class size, which measures actual students in a classroom.

A school with 500 students and 30 full-time teachers.