Pupil-trained teacher ratio


Average number of pupils per trained teacher at a given level of education.

Data source

Administrative data from schools and other organized learning centres.

Calculation method

Total number of pupils and students in the relevant level is divided by the number of trained teachers in the same level.

Data required

Number of pupils and trained teachers at each level of education


The higher the pupil- trained teacher ratio, the lower the relative access of pupils to trained teachers. Results can be compared with established national norms on the number of pupils per trained teacher for each level of education. In calculating and interpreting this indicator, one should take into account the existence of part-time teaching, school-shifts, multi-grade classes and other practices that may affect the precision and meaningfulness of pupil-teacher ratios.


The “ideal” pupil-trained teacher ratios may depend on a wide variety of complex factors, including the age and academic needs of the pupils represented in the ratio (younger children or those with special educational needs typically require more time, attention, and instructional support from teachers) or the experience, skill, and effectiveness of the teachers (highly skilled teachers may be able to achieve better academic results with larger classes than less skilled teachers with smaller classes). Pupil-teacher ratios are not equivalent to the average class size which, in general, has higher values. It is important to note that national teacher training requirements can vary from one country to the next. Further work would be required if a common standard for professional trainings is to be applied across countries.


Pupil-teacher ratios are generally used to measure teacher workloads and human resource allocations in educational institutions, and to give a general indication of the average amount of time and individual attention a pupil is likely to receive from teachers. Since well-trained teachers play a key role in ensuring the quality of education provided, the pupil-trained teacher ratio is considered an important determinant of learning outcomes and an indicator of the overall quality of an education system.

Quality standards

When feasible, the number of part-time teachers should be converted to ‘full-time equivalent’ numbers of teachers; a double-shift teacher should be counted twice, etc. Ideally, all staff involved in direct classroom-teaching roles should be included in the calculations.

Types of disaggregation

Level of education and type of institution (public/private)