Square Root Curve Calculator

Calculate square root curved grades for fair grading. The square root curve helps correct for difficult exams by giving lower scores a larger boost. Use our free calculator to convert raw percentage grades to curved grades using the square root curve formula.

Grade Calculation

Results

Enter a grade and click calculate to see results

About Square Root Curving

  • • Formula: Curved Grade = 10 × √(Raw Grade)
  • • Purpose: Gives lower scores a larger boost than higher scores
  • • Maximum: Curved grade cannot exceed 100
  • • Fairness: Helps correct for overly difficult exams

Formula and Examples

Square Root Curve Formula

SRG = √(G) × 10

Where:
SRG = Square Root Curve Grade (%)
G = Student's percentage grade (%)

The inverse formula to convert curved grades back to raw grades:
Raw Grade = (Curved Grade ÷ 10)²

Example Calculations

Raw: 64% → Curved: 80%
Raw: 81% → Curved: 90%
Raw: 100% → Curved: 100%
Raw: 36% → Curved: 60%