Grade Curve Calculator

When to use the Grade Curve Calculator

• Use it when your instructor describes a simple add-points curve or a top-score scaling method.
• Use it to compare how different curve assumptions change your score before the official grade is posted.
• Use it as a planning tool only when you know the curve rule; do not use it to guess a distribution-based curve.

Grade curve mistakes to avoid

• Using add-points mode when the instructor actually scales scores to the highest score.
• Entering the class average as the top score in top-score mode.
• Forgetting that scores may be capped at 100% or rounded differently.
• Assuming every student receives the same benefit when the instructor uses letter-grade cutoffs or percentiles.
• Treating a hypothetical curve as an official grade before the instructor announces the rule.

How to read a curved score

The result shows one simple curve model applied to your input. Real curves may depend on class distribution, cutoffs, exam difficulty, and instructor judgment, so use the result as a scenario rather than a promise.

Real student situations

Choose the curve mode

• Use add-points mode for a fixed bonus such as +5 points for everyone.
• Use top-score mode when the highest score is treated as the new maximum.
• Do not use this calculator for percentile ranks, z-scores, class average targets, or letter-grade boundary shifts.
• Check whether the curved score is capped at 100 before comparing scenarios.

When the result can differ

• Class distribution, exam question removal, partial credit review, letter cutoffs, maximum caps, and instructor discretion can all change the official curved grade.