Grade Curve Calculator
Enter your raw score and the highest score in the class to see your curved grade using the common top-score method, where the highest mark is lifted to full marks and everyone gets the same boost.
A curve adjusts raw scores upward when a test turns out harder than expected. The most common classroom method takes the highest score in the class, adds enough points to make it full marks, and gives every student that same number of points.
How the top-score curve works
Find the gap between the maximum possible score and the highest score anyone got, then add that gap to your own score.
Points added = Maximum − Highest score
Curved score = Your score + Points added
Curved % = Curved score ÷ Maximum × 100
Curved score = Your score + Points added
Curved % = Curved score ÷ Maximum × 100
| Method | How it curves |
|---|---|
| Top-score (this tool) | Highest mark becomes 100%; everyone gets the same points added |
| Flat scale | A fixed number of points is added to every score |
| Square-root | Curved % = 10 × √(raw %); helps lower scores more |
Worked example
You scored 72, the class high was 88, out of 100:
| Points added = 100 − 88 | 12 |
| Curved score = 72 + 12 | 84 |
| Curved percentage | 84% |
Frequently asked questions
How do you curve a grade to the highest score?
Subtract the highest score from the maximum possible, then add that difference to every student's score. The top student ends at 100% and everyone rises by the same amount.
Does a curve always raise grades?
A top-score or flat curve only raises or keeps grades the same — it never lowers them. Some statistical curves can move scores in both directions.
What if the highest score is already full marks?
Then the gap is zero, so no points are added and scores stay the same.
Related calculators
An estimate of a common curving method. Your instructor may use a different approach — always check how your class is actually graded.