UPSC CSE Syllabus & Exam Pattern

Complete three-stage structure of UPSC CSE — Prelims, Mains and Interview — with paper-wise syllabus and marks breakdown.

Last reviewed: August 2026

The Three-Stage Structure

UPSC CSE is conducted in 3 stages: Prelims (objective screening), Mains (written), and the Personality Test (Interview).

Stage 1 — Prelims
Objective/MCQ, 2 papers, 400 marks total. Only GS Paper-I counts for the cutoff; CSAT is qualifying. Prelims marks do not count toward final ranking.
Stage 2 — Mains
9 written papers, of which 7 count toward merit. Written merit = 1750 marks.
Stage 3 — Interview
Personality Test worth 275 marks. Final merit = 1750 + 275 = 2025 marks.
Prelims is only the gateway
Final rank is decided by Mains (1750) + Interview (275) = 2025 marks. Prelims marks are used only for screening into Mains.

Prelims — Exam Pattern

Prelims is a one-day screening examination with two papers.

PaperSubjectQuestionsMarksTimeNature
Paper IGeneral Studies1002002 hoursMerit for cutoff
Paper IICSAT802002 hoursQualifying
Total1804004 hours
CSAT needs 33% minimum
200 x 33% = 66 marks — you must score at least 66/200 in CSAT. Do not assume 'qualifying' means you can skip preparing it; you need enough practice to safely cross 66.

Prelims GS Paper-I — Syllabus Areas

GS Paper-I is the most important Prelims paper. Its official syllabus spans current events, history, geography, polity, economy, environment and science & technology.

Current Events
National and international importance: government schemes, legislation, Supreme Court judgments, international organizations and relations, reports and indices, environment, S&T, economy, personalities, awards, places in news, defence.
History of India
Ancient (Indus Valley, Vedic period, Buddhism, Jainism, Mauryan, Gupta, Sangam age, art and culture), Medieval (Delhi Sultanate, Mughals, Vijayanagara, Bhakti and Sufi movements, Marathas, architecture, administration) and Modern India.
Indian National Movement
Formation of INC, Moderates vs Extremists, Partition of Bengal, Swadeshi, Home Rule, Gandhian movements (Champaran, Kheda, Non-Cooperation, Civil Disobedience, Dandi March, Quit India), Round Table Conferences, Government of India Acts, INA, Cabinet Mission, Independence and Partition. UPSC asks conceptual, analytical questions — not merely dates.
Indian & World Geography
Physical geography (earth's interior, plate tectonics, earthquakes, volcanoes, climate, monsoon, cyclones, ocean currents, soils), Indian geography (Himalayas, plains, plateau, rivers, agriculture, minerals, industries, population) and world geography (continents, mountains, rivers, deserts, climate regions).
Polity & Governance
One of the highest-value areas: Constitution (Preamble, FRs, DPSP, amendments, Basic Structure), Union Government, Parliament, Judiciary, federalism, constitutional bodies (EC, UPSC, CAG, Finance Commission), statutory bodies (NHRC, CIC, CVC, Lokpal, NGT) and local government (73rd/74th Amendments).
Economy
Understand how the Indian economy works: GDP/GNP/NNP, inflation, deficits, BoP; banking (RBI, repo, CRR, SLR, NPAs); government finances (budget, taxation, fiscal policy, public debt); external sector (trade, forex, FDI/FPI, WTO); development (poverty, inclusive growth, financial inclusion, infrastructure).
Environment & Ecology
Ecology basics (ecosystem, food chains, pyramids, succession), biodiversity (endemic, keystone, invasive, threatened species), conservation (National Parks, Sanctuaries, Biosphere Reserves, Tiger Reserves, Ramsar Sites), issues (climate change, pollution, desertification) and conventions (UNFCCC, Paris Agreement, CBD, Ramsar, CITES, Montreal Protocol).
Science & Technology
Application-oriented: biology (diseases, vaccines, genetics), biotechnology (CRISPR, gene therapy, stem cells, mRNA), space (ISRO, satellites, launch vehicles, missions), physics (nuclear, semiconductors) and emerging tech (AI, ML, quantum computing, blockchain, nanotech, robotics, 5G/6G, cybersecurity).

CSAT — Prelims Paper II

CSAT is qualifying, but the syllabus is still substantial.

Mains — The Real UPSC Examination

Mains is where the competition becomes much more serious. It consists of 9 papers, of which 7 count for merit.

PaperSubjectMarksCounted for Merit?
Paper AIndian Language300No (qualifying)
Paper BEnglish300No (qualifying)
Paper IEssay250Yes
Paper IIGS-I250Yes
Paper IIIGS-II250Yes
Paper IVGS-III250Yes
Paper VGS-IV250Yes
Paper VIOptional-I250Yes
Paper VIIOptional-II250Yes
Total Merit1750

Personality Test adds 275 marks, so the final merit total is 1750 + 275 = 2025 marks. Paper A is one Indian language chosen from those specified by UPSC (e.g. Marathi, Hindi, Bengali, Gujarati, Kannada, Malayalam, Tamil, Telugu, Urdu, Sanskrit) and requires only the prescribed minimum. Paper B (English) tests comprehension, precis writing, usage, vocabulary, short essays and basic language skills — its marks are not added to final merit.

Essay Paper (250 marks)
Topics can involve philosophy, society, politics, economy, technology, environment, education, women, democracy, ethics and development. UPSC expects: Introduction, Arguments, Examples, Counter-view, Analysis, Way forward, Conclusion. An essay is NOT a GS answer stretched to several pages.

The Four GS Papers of Mains

GS-I — Heritage, History, Geography, Society (250)
Indian culture (art, architecture, literature, music, dance, paintings), modern history from the 18th century and the freedom struggle, world history (Industrial Revolution, World Wars, American/French/Russian Revolutions, colonialism, decolonization), Indian society (diversity, women, population, urbanization, globalization, communalism, regionalism, secularism) and geography (physical geography, resources, industries, geographical phenomena).
GS-II — Polity, Governance, Social Justice, IR (250)
Heavily focused on Constitution + governance + current affairs: polity (Parliament, Executive, Judiciary, federalism, constitutional bodies), governance (transparency, accountability, e-governance, citizen charters, NGOs, SHGs, civil society), social justice (health, education, poverty, vulnerable sections, welfare schemes) and IR (India-USA/Russia/China/EU/Japan/Africa, neighbourhood, UN, WTO, IMF, World Bank, regional organizations).
GS-III — Economy, S&T, Environment, Security (250)
A very broad paper: economy (growth, employment, inclusive growth, budget, infrastructure, investment), agriculture (cropping patterns, irrigation, MSP, subsidies, food processing, PDS), science & technology (emerging tech, space, biotech, AI, robotics, IT), environment (conservation, climate change, pollution, EIA) and internal security (terrorism, cybersecurity, money laundering, organized crime, border security, insurgency, extremism).
GS-IV — Ethics, Integrity & Aptitude (250)
Different from other GS papers: ethics and human interface, human values, attitude, emotional intelligence, moral thinkers, ethics in public administration; integrity, probity, transparency, accountability, public service values; aptitude (objectivity, impartiality, non-partisanship, dedication, empathy, compassion) — plus case studies.
GS-IV case studies are extremely important
You are given practical administrative situations (e.g. as District Collector, a scheme bridge has serious defects and the contractor is politically influential). You must identify stakeholders, ethical issues, options, pros/cons, the best course of action and its justification.

Optional Subject & Personality Test

You choose ONE optional subject with two papers of 250 marks each — 500 marks in total, a huge component of your final ranking. UPSC lists optionals including Agriculture, Anthropology, Geography, History, Law, Mathematics, Political Science & International Relations, Public Administration, Sociology and literature subjects. Popular choices include Geography, History, Sociology, Anthropology, PSIR, Public Administration, Philosophy, Economics, Mathematics and literature subjects.

How final rank is decided
Candidate A with Mains 950/1750 + Interview 180/275 = 1130/2025 ranks higher than Candidate B with Mains 900 + Interview 220 = 1120. Mains + Interview alone determine the final ranking.

Prelims vs Mains — The Biggest Differences

FeaturePrelimsMains
TypeObjectiveDescriptive
Main purposeScreeningRanking
QuestionsMCQWritten answers
Negative markingYesNo
Current affairsImportantVery important
Static syllabusImportantVery important
Answer writingNoYes
OptionalNoYes
Total merit marks01750
InterviewNoAfter qualification
Prelims game
Knowledge + elimination + accuracy + revision + test practice.
Mains game
Knowledge + understanding + analysis + answer writing + examples.
Interview game
Personality + awareness + balanced thinking + communication.

The Whole Syllabus in One Page

The syllabus is your master document
Don't prepare randomly from YouTube, Telegram, newspapers and books. Always follow: Syllabus > Previous Year Questions > Sources > Notes > Revision > Tests. UPSC's own previous-year papers show the actual level and style of questions.

More UPSC CSE Guides

UPSC Civil Services Examination (CSE) overview · All government exams · Study material