How it's calculated
The calculator keeps the thirds exact and rounds only the final score to two decimals.
Estimate only. Official results, marks and eligibility are decided by the Union Public Service Commission. Verify on the official website.
Worked example
GS Paper I with 55 right and 25 wrong: 110 − 25 × 2/3 = 93.33 out of 200.
CSAT with 30 right and 10 wrong: 75 − 10 × 5/6 = 66.67, which clears the 33% qualifying mark of 66.
When guessing helps
With four options and a one-third penalty, a blind guess averages out to zero. In GS Paper I it is a 1-in-4 chance of +2 against a 3-in-4 chance of −2/3: (1/4 × 2) − (3/4 × 2/3) = 0. If you can rule out one option, the average turns positive. This is arithmetic, not a strategy tip.
Frequently asked questions
What is the negative marking in UPSC prelims?
One-third of the marks for that question is deducted for each wrong answer. In GS Paper I (2 marks a question) that is 2/3 of a mark; in CSAT (2.5 marks a question) it is 5/6 of a mark. Marking more than one answer counts as wrong. Blank questions carry no penalty.
How many questions are in UPSC prelims 2026?
GS Paper I had 100 questions and GS Paper II (CSAT) had 80 questions, each paper for 200 marks and two hours, as printed on the 2026 question booklets.
What is the qualifying mark for CSAT?
33%, i.e. 66 out of 200. CSAT is qualifying only; its marks are not added to your merit.
What is the prelims cut-off?
The Commission decides the GS Paper I qualifying marks after the exam, so the cut-off changes every year. Only candidates who also clear 33% in CSAT are considered.
Do prelims marks count in the final rank?
No. Prelims is a screening test. Final merit is based on the Main examination (written) and the interview.
Sources
- UPSC Examination Notice No. 05/2026-CSP dated 04-02-2026: Civil Services (Preliminary) Examination, 2026, Union Public Service Commission (UPSC)
- UPSC CSP 2026 General Studies Paper-I question booklet (instructions: 100 items, 200 marks, all items equal marks, one-third penalty); notice Appendix I, Note II, Union Public Service Commission (UPSC)
- UPSC CSP 2026 General Studies Paper-II (CSAT) question booklet (instructions: 80 items, 200 marks, one-third penalty); notice Section II(A) note (ii), Union Public Service Commission (UPSC)