Donaldson R F T-Score Calculator
Put any score on the standard T-scale (mean 50, standard deviation 10) used in psychological and educational testing.
–T-score
–Z-score
–Percentile
What is a T-score?
A T-score rescales a z-score so that the average is 50 and one standard deviation is 10 points: T = 50 + 10 × z, and back again with z = (T − 50) ÷ 10. It avoids negative numbers and decimals, so results are easier to report — a T-score of 65 is 1.5 standard deviations above the mean. The percentile assumes a normal distribution. This is the standardised T-score used in testing; it is not the t-statistic from a t-test and not the bone-density T-score, which uses its own reference population.