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Flat Points Curve Calculator

Curve a test score by adding a fixed number of bonus points, capped at 100%.

Result

Curved Score
83%
Letter Grade
B

About the Flat Points Curve

The Flat Points Curve Calculator applies a straightforward grading curve by adding a fixed number of bonus points to a raw test score, capped so the curved result never exceeds 100%. It is meant for instructors or students checking what a flat-point curve would do to a specific score.

How It Works

You enter the raw score as a percentage and the number of flat points the instructor is adding to every score. The calculator adds the points to the raw score, capping the sum at 100%, then converts the curved percentage into a letter grade using standard grade bands.

Curved Score = min(rawScore + pointsToAdd, 100); Letter Grade is assigned from the curved percentage (A at 93+, A- at 90+, B+ at 87+, B at 83+, B- at 80+, C+ at 77+, C at 73+, C- at 70+, D at 60+, F below 60)

Examples

Typical mid-range score

A student scores 78% raw and the instructor adds a 5-point flat curve. The curved score is 78 + 5 = 83%, which falls in the B band.

Score near the ceiling

A student scores 97% raw with the same 5-point curve applied. Since 97 + 5 = 102 exceeds 100, the curved score is capped at 100%, and the calculator notes that the cap was reached.

Advantages

  • Applies the cap at 100% automatically, preventing an unrealistic curved score above the maximum possible grade
  • Converts the curved percentage directly into a letter grade, saving a separate lookup step
  • Makes it simple to compare how the same flat-point curve affects a low score versus a high score

Common Mistakes

  • Assuming a flat points curve helps every student equally in relative terms, when in absolute points it is equal but it helps low scorers proportionally more toward passing thresholds
  • Not accounting for the 100% cap when estimating how much a curve will raise students who were already close to a perfect score
  • Applying flat-point curve logic when the actual grading scheme uses a different curve method, such as a square-root curve, which produces different results for the same raw score

Edge Cases to Watch For

  • The curved score is capped at 100%, so a raw score plus the added points that would exceed 100 is truncated, and the calculator flags this with a note that the score hit the maximum.
  • Because every score receives the same flat point addition, a curve large enough to push a high scorer to exactly 100% delivers no additional benefit to that student beyond the cap.
  • The letter grade thresholds used are fixed standard bands and may not match the specific cutoffs an individual instructor or institution uses.

Common Use Cases

  • Instructors deciding how many flat points to add to bring a class average up to a target level
  • Students checking what their curved grade and letter grade will be once an announced point curve is applied
  • Teaching assistants recalculating a batch of scores after an instructor announces a flat-point adjustment
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

How is a flat points curve different from the square-root curve?

A flat points curve adds the same fixed number of points to every score regardless of how high or low it was, which helps everyone equally in absolute terms. The square-root curve instead applies a formula that boosts lower scores much more than higher ones, so the two methods can produce noticeably different results for the same class.

Conclusion

This calculator applies the arithmetic of a flat-point curve, addition plus a 100% ceiling, and reports both the curved percentage and its letter grade. It reflects one specific curving method among several, so the result only applies when the flat-points approach is the one actually being used.