UPSC Prelims Syllabus, Subject by Subject

Prelims is where most UPSC journeys end — not because the syllabus is impossible, but because it is objective, negatively marked, and unforgiving of vague preparation. This page lays out the complete Prelims syllabus for the 2027 cycle: both papers, every subject, the topic counts, and the arithmetic that decides attempts.

Prelims 2027 is scheduled for Sunday 23 May 2027, per UPSC's Calendar 2027 (as on 20 May 2026), which also lists the notification for 13 January 2027 and 2 February 2027 as the last date for applications. Treat those dates as provisional: the calendar says they are "liable to alteration", and the 2026 notification came out on 4 February 2026, three weeks after the 14 January date in Calendar 2026. Until the 2027 notice is issued, the official syllabus is the one in the CSE 2026 notice, which is the text used below.

The two Prelims papers

The Preliminary Examination is a single day with two objective papers. Every question is multiple-choice, machine-marked, and set bilingually in English and Hindi.

Paper	Questions	Marks	Duration	Negative marking	Role
GS Paper I (General Studies)	100	200	2 hours	−0.66 per wrong answer	Decides the cutoff. Your GS-I score alone determines whether you reach Mains.
Paper II (CSAT)	80	200	2 hours	−0.83 per wrong answer	Qualifying only. Score 33% (66.67 marks) and it has done its job.

The question counts are as printed on UPSC's official Paper I and Paper II booklets from the 24 May 2026 Prelims: 100 and 80 items, two hours and 200 marks each, every item printed in Hindi and English, and one-third of a question's marks deducted for a wrong answer.

Two structural facts shape everything else. First, Prelims marks do not count in the final merit — this stage exists only to screen candidates for Mains, so the goal is clearing the cutoff safely, not topping the paper. Second, a wrong answer costs one-third of the question's marks, which makes blind guessing a losing strategy and intelligent elimination a scoring skill in its own right. The full paper-by-paper structure of all three stages is on our exam pattern page.

The official GS Paper I syllabus

UPSC's notified syllabus for Paper I is seven famously compact lines:

• Current events of national and international importance
• History of India and the Indian National Movement
• Indian and World Geography — physical, social and economic geography of India and the world
• Indian Polity and Governance — Constitution, political system, Panchayati Raj, public policy, rights issues
• Economic and Social Development — sustainable development, poverty, inclusion, demographics, social sector initiatives
• Environmental ecology, biodiversity and climate change (no subject specialisation required)
• General Science

Seven lines, and each one hides a subject's worth of material — which is exactly why aspirants drown in "comprehensive" books. The way out is to expand those lines into a finite topic tree and then finish the tree. Always read the authoritative text in the latest official UPSC notification, which until the 2027 notice is the CSE 2026 notice (Examination Notice No. 05/2026-CSE, dated 4 February 2026); what follows is that syllabus organised the way UPSCGenie actually teaches it.

GS Paper I, expanded into a teachable tree

The site-wide tree covers 255 topics across 8 subjects. Here is the Prelims GS portion, with links to each subject's complete topic-by-topic page:

Subject	What GS-I actually asks	Topics
History	Ancient and Medieval India, the full Modern India arc from Conquest to Freedom, constitutional development under British rule, Art & Culture, and post-Independence consolidation. Culture and Modern India carry the weight.	65
Polity & Governance	Constitutional framework, Fundamental Rights, DPSP, Union and State government, Judiciary, federalism, constitutional and statutory bodies, governance and representation. The most predictable, highest-yield subject in the paper.	56
Economy	National income basics, money and banking, public finance, the external sector, growth and development — tested conceptually and through schemes and current developments.	37
Environment & Ecology	Ecology fundamentals, biodiversity, pollution, climate change, and conservation architecture — a heavyweight scoring area in recent papers, dense with current-affairs hooks.	32
Geography	Physical geography, Indian and world geography, human and economic geography, and map-based questions that reward atlas time over prose time.	25
Science & Technology	General science plus what's in the news: space and defence, biology and health, emerging and digital technologies. Tested as applied awareness, not textbook depth.	15
Current Affairs	National, international, economy, environment, science, awards — roughly a quarter of the paper connects to the last 12–18 months, usually threaded through a static topic.	9 groups

Every linked page lists the complete topic tree for that subject, and every topic has a free source-cited lesson in the app.

Note what the current-affairs row implies: you cannot "finish" current affairs, and you cannot skip it. It is a daily habit that continuously attaches itself to the static tree — which is why UPSCGenie runs it as a daily brief and revision sprint rather than a stack of monthly PDFs.

The CSAT Paper II syllabus

The official Paper II areas:

• Comprehension
• Interpersonal skills, including communication skills
• Logical reasoning and analytical ability
• Decision-making and problem-solving
• General mental ability
• Basic numeracy — numbers and their relations, orders of magnitude (Class X level)
• Data interpretation — charts, graphs, tables, data sufficiency (Class X level)

"Class X level" and "qualifying only" convince many aspirants to ignore CSAT until the final month. That mistake eliminates candidates every single year — people who cleared the GS cutoff and failed a paper they never practised. The maths is school-level; the speed under pressure is not, especially if you are years away from your last maths classroom. A steady weekly dose of CSAT previous-year papers from early in preparation is cheap insurance; our negative-marking strategy guide covers the attempt discipline both papers need.

Prelims vs Mains: same subjects, different exam

Polity, History, Geography, Economy and Environment all appear again in the four Mains GS papers — but as analytical written answers instead of one-correct-option questions. Prepare the Prelims tree properly and you have quietly built most of your Mains GS base; what Mains adds is Essay, Ethics (GS-IV), your optional subject, and the answer-writing craft that turns knowledge into marks.

How to actually cover the Prelims syllabus

1. Sequence, don't parallel-read. Foundations first — Polity → Modern History → Geography → Economy → Environment → Science & Tech — with CSAT practised weekly throughout. Most first-timers should open with Polity: high-yield, logical, and it makes the daily news legible.
2. A topic isn't covered until you've answered questions on it. Attach previous-year questions to every topic as you finish it — our subject-wise PYQ analysis shows exactly where the paper concentrates.
3. Build the current-affairs habit on day one, not in the final six months.
4. Protect the last weeks for revision and mock tests. A plan that teaches until exam day is a plan that fails; the cutoff is cleared in revision, and attempt strategy is trained in mocks.
5. Work backward from your exam date. Our study-plan guide shows the arithmetic; the app's planner builds your week-by-week schedule from your date, hours and weak areas.

Frequently asked questions

Is the UPSC Prelims syllabus different from the Mains syllabus?

The subjects overlap heavily but the papers test them differently. Prelims is objective — one correct option, negative marking — while Mains asks the same Polity, Economy, Geography and Environment material as analytical written answers. Prelims preparation done properly builds most of your GS Mains base; Essay, Ethics (GS4) and your optional subject are Mains-only additions.

How many topics does the UPSC Prelims syllabus contain?

In UPSCGenie's teaching tree the Prelims syllabus breaks into 255 teachable topics across 8 subjects: History (65), Polity & Governance (56), Economy (37), Environment & Ecology (32), Geography (25), Science & Technology (15), CSAT (16), and continuously-updated Current Affairs.

Do Prelims marks count in the final UPSC merit list?

No. Prelims is purely a screening stage — its marks decide only whether you qualify for Mains. The final merit is calculated from the Mains written papers and the Interview. That is why Prelims strategy is about clearing the cutoff safely, not maximising the score.

Is CSAT really only qualifying?

Yes — you need 33% (66.67 out of 200) and CSAT marks are not counted further. But "qualifying" is not "ignorable": candidates who clear the GS cutoff and fail CSAT are eliminated every year, and the paper's numeracy and reasoning need regular practice, especially for candidates from non-maths backgrounds.

When should I start covering the Prelims syllabus for the 2027 exam?

Prelims 2027 is scheduled for 23 May 2027 per UPSC's Calendar 2027 (as on 20 May 2026), which leaves about 34 weeks from late September 2026. A comfortable first attempt needs 10–12 months for the static syllabus plus revision, so a start now has to be compressed: tighter sequencing, and the final weeks kept for revision and mock tests. UPSCGenie's planner builds the schedule backward from your exam date and available hours per day.

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