How negative marking scoring works
Score = (correct × marks per correct) − (wrong × penalty per wrong). Questions left unattempted contribute zero and are not penalised. Different exams use very different ratios — always check your specific exam's official marking scheme rather than assuming a default.
Should you guess?
The expected value of a guess depends on the penalty ratio and how many options you can eliminate. On a four-option question with a −0.25 penalty, a fully random guess has an expected value of roughly zero; eliminating even one wrong option tips it positive.
Frequently asked questions
- Which exams use which scheme?
- Marking schemes vary by exam and even by year, so this tool lets you pick a common preset or enter your exam's exact scheme manually — always confirm against the official notification.
- Can this predict my rank or percentile?
- No — this calculates raw score only. Percentile depends on that year's difficulty and other candidates' performance, which this tool doesn't estimate.