Bell Curve Grade Calculator
Assign letter grades on a normal curve.
Enter your values
Results update instantly as you type — no submit needed.
Results
- Curved score
- 80.5%
- Letter grade
- B-
- Z-score
- 0.55
- Points gained
- 16.5
Quick answer
Curving shifts scores so the class mean lands on a chosen target while preserving the spread.
Curved = target + (score − mean) × (targetSD ÷ SD)
How to use the Bell Curve Grade Calculator
- 1Enter the raw score and the class statistics.
- 2Choose the target mean and spread.
- 3Read the curved score and letter grade.
Frequently asked questions
Is curving fair?
It normalises for a hard paper but also caps how many students can earn top grades.
What target mean is common?
Many instructors curve to a 75 mean.