Grade Curve Calculator

Take the highest score in the class off the maximum, then add that difference to every score. The top paper lands on the maximum and the gap between any two students stays exactly where it was.

With raw scores of 58, 64, 71, 79, 86 the top is 86, so every score gains 14 points and the set becomes 72, 78, 85, 93, 100. The class average moves from 71.6% to 85.6%, and the lowest paper goes from letter F to letter C.

A top score already on the maximum adds nothing, so a class with one perfect paper is left where it stands.

Divide the score by the maximum, take the square root, then multiply by the maximum again. Every score below the top of the scale rises, and the further below it a score sits the more it rises.

The same raw scores become 76.16, 80, 84.26, 88.88, 92.74. The lowest paper gains18.16 points and the highest gains 6.74, which is what makes this curve the one to pick when the bottom of the class needs the help. A zero stays a zero and a score on the maximum stays there, so the rank order never changes and the class average moves from 71.6% to 84.41%.

A curved score is still one score inside a course, and the weight it carries against homework and the final is the sum the grade calculator runs.

The two methods answer different problems. Linear is the one for a test where the top paper fell short, and square root is the one for a test where the whole class did.

Letters from the standard 10-point scale. Source: Academic grading in the United States, read 2026-09-20.

Which letter a curved score earns depends on the cutoffs the school publishes, which the grading scale page sets out, and the raw score going into the curve is whatever the test grade calculator returned for the paper.