Negative Marking Score Calculator (UPSC, SSC, JEE, NEET, Banking — Attempts & Accuracy)

How it works

score = correct × (+m) − wrong × (−p) · break-even accuracy = p ÷ (m + p) (¼ negative on +1 → 20%; ⅓ on +2 → 25%; ½ on +2 → 20%) · expected marks per attempt = a·m − (1 − a)·p · attempts for target = target ÷ (a·m − (1 − a)·p) · blind-guess EV = m ÷ k − p × (k − 1) ÷ k

Negative marking turns every question into a small bet: attempt it and you win the full marks with probability equal to your accuracy, or lose the penalty otherwise. The expected value of an attempt is positive only above a break-even accuracy set purely by the ratio of penalty to reward — a quarter-mark penalty on one mark needs twenty percent, a third on two marks needs twenty-five — and since even a blind guess among four options is right a quarter of the time, guessing is neutral or better in most Indian exam patterns and clearly positive once a single option can be eliminated. The practical consequence is that scores are raised by attempting more at steady accuracy rather than by the fear of penalties.

Worked example

In UPSC Prelims (2 marks, −0.667) attempting 80 questions at 72% accuracy gives 58 right and 22 wrong — 101.3 marks, above a 95 cutoff. The break-even accuracy is only 25%, so each attempt at that accuracy is worth about 1.27 marks; hitting 95 needs 75 attempts, and even a blind guess has an expected value of exactly zero at four options, turning positive (+0.22) once one option is ruled out.

Frequently asked questions