A T-score is a standard score with mean 50 and standard deviation 10. A T-score of 60 means you are one standard deviation above the mean.

When are T-scores used?

T-scores are commonly used in psychological testing, educational assessments, and clinical evaluations to compare individuals to a reference group.

What is the range of T-scores?

Most T-scores fall between 20 and 80 (within 3 standard deviations). A T-score of 50 is exactly average.

Convert a raw score to a standard score (T-score) with a mean of 50 and standard deviation of 10 for educational testing.

Your Score

Group Mean

Standard Deviation

T-Score (Standard Score)

58.8

Z-Score0.88

Deviation from Mean7.0

T-Score (Standard Score) vs Your Score

A T-score rescales your z-score to a distribution with mean 50 and standard deviation 10.

T-Score = 50 + 10 x Z

Where Z = (Score - Mean) / Standard Deviation

T-scores eliminate negative numbers and decimals, making interpretation easier.

A student scores 82 in a group with mean 75 and standard deviation 8.