What is Grade Curve Calculator?
Curving a grade applies a formula to raw scores to raise the class average. This calculator models the three most common methods. A flat curve adds the same number of points to everyone, which lifts the whole distribution but changes nothing about the gaps between students. A square-root curve — the classic 10×√score — helps low scores more than high ones, which is why it is used when an exam was too hard for most of the class: 49% becomes 70% while 81% only rises to 90%. A gap-recovery curve returns a chosen percentage of the distance between the score and 100%, which compresses the top of the range as well. All three are calculated against the same raw score so you can compare them side by side.
Common Uses for Grade Curve Calculator
- See the effect of a proposed curve before announcing it to a class
- Check whether a square-root curve unfairly helps the top of the class
- Convert a curved score into a letter grade for the gradebook
- Compare a flat +5 curve against a 50% gap-recovery curve
Choosing a curve
Ask what went wrong. If the exam was well written but hard, a square-root or gap curve rewards the students who attempted the hardest material. If a single question was impossible, dropping it and redistributing is cleaner than any curve. If the class simply needs a bump for consistency with past years, a flat curve is the least disruptive — it keeps the shape of the distribution intact.
Curves and letter grades
A curve changes the percentage, and the letter grade follows the percentage — unless the class is graded strictly on a curve where a fixed share receives each letter. In that case the percentage matters less than the rank, and this calculator's output is an intermediate step rather than the final grade.