How grade curve calculator works
A grading curve adjusts a whole set of scores at once when an exam turns out harder than intended. There is no single "the curve" — there are three standard moves, and this tool implements all three on the same list of scores so you can compare them before choosing.
Flat add: every score gains the same N points, capped at the maximum (100 by default). It lifts the whole class uniformly and preserves all differences. Linear rescale: the current lowest and highest scores are stretched onto a new range (default 0-100), which raises the bottom of the class the most and can be capped with a custom target range such as 70-90. Top-score adjust: every score is scaled proportionally so the current top score becomes 100 — the classic "the top scorer sets the scale" curve.
Paste scores separated by commas, spaces or newlines. The result shows every curved score rounded to one decimal, its delta versus the original, and the class statistics (min, max, mean) before and after — so you can see exactly who gained what before you commit. The linear method also reports the slope and intercept of the line it applied.
One caution the tool enforces honestly: a curve can lower as easily as raise. A flat negative add is accepted (and every result is clamped to [0, cap]), and a linear rescale to a narrower range pulls the top scores down. If the goal is only to help the class, flat adds and top-score adjustments with a target of 100 keep every result at or above the original.