Convert raw scores into percentiles and OECD proficiency levels.
Standardized Z-Score:–
Global Percentile Rank:–
OECD Proficiency Level:–
*Results are based on standard normal distribution models used in PISA psychometrics.
What is a PISA Score?
The Programme for International Student Assessment (PISA) is a worldwide study by the OECD that measures 15-year-old students' scholastic performance on mathematics, science, and reading. Unlike raw percentages, PISA scores are standardized to have an average of 500 and a standard deviation of 100 across OECD countries.
Understanding PISA Proficiency Levels
PISA classifies student performance into six main proficiency levels. Level 2 is considered the "baseline" level of proficiency required to participate effectively in modern society.
Level 6 (Over 708 points): Students can communicate complex reasoning and demonstrate advanced mathematical or scientific thought.
Level 4 (559 to 633 points): Students can work effectively with explicit models for complex concrete situations.
Level 2 (407 to 482 points): The baseline where students begin to demonstrate competencies that allow them to participate actively in life.
Below Level 1 (Under 335 points): Students have difficulty performing the simplest tasks.
Realistic Example:
If a student in Singapore scores 620 in Mathematics, and the OECD mean is 500 with a standard deviation of 100:
The Z-Score is (620 – 500) / 100 = 1.2.
This places the student in the 88th percentile globally.
The student achieves Proficiency Level 4.
How This Calculator Works
This tool uses the Gaussian error function approximation to calculate the percentile rank based on the score distribution. It identifies the proficiency level based on the standardized thresholds defined by the OECD for core PISA subjects.