Test Score Calculator

Converting a raw mark to a percentage is trivial arithmetic, but the surrounding decisions are where the interesting parts sit. The first is how much a single question is worth, which is entirely determined by test length. On a twenty-question test each item carries five percent, so two careless errors drop you a full letter grade. On a hundred-question test the same two errors cost two percent and are nearly invisible. Short tests are far higher variance, which is worth knowing before concluding much from one result.

Negative marking changes the strategy rather than just the score. When wrong answers carry no penalty, guessing always has positive expected value and leaving anything blank is simply wasted opportunity. When wrong answers deduct a fraction of a mark, there is a break-even point: with a quarter-mark penalty on five options, random guessing is exactly neutral, and guessing only becomes worthwhile once you can eliminate at least one option. The SAT abandoned its penalty in 2016 for precisely this reason — it was testing risk tolerance alongside knowledge.

Curves come in several forms that are frequently conflated. A flat curve adds the same number of points to everyone. A scaled curve maps the highest score to one hundred percent and adjusts the rest proportionally. A true curve fits grades to a predetermined distribution, meaning your grade depends on how everyone else performed rather than on any absolute standard. These produce very different outcomes from the same raw marks, so it is worth knowing which one your course uses.