What is the Detailed Syllabus of the IAS Prelims Examination?

If you are serious about cracking the UPSC Civil Services Examination, the first step is to search “What is the IAS Prelims Syllabus”. Many aspirants start preparation without fully understanding what UPSC actually asks. This leads to random study, unnecessary books, and frustration.

In this detailed guide, we will break down:

• The structure of the UPSC exam
• The complete and official syllabus of IAS Prelims
• Subject-wise explanation of GS Paper I
• Detailed CSAT syllabus
• Important and frequently asked areas
• Step-by-step preparation strategy for each subject
• Practical tips and common mistakes

Let’s begin from the foundation.

1. Overview of the UPSC Civil Services Examination

The Civil Services Examination (CSE) conducted by UPSC has three stages:

1. Preliminary Examination (Prelims) – Screening stage
2. Main Examination (Mains) – Descriptive written exam
3. Personality Test (Interview)

Nature of Prelims

• Objective type (MCQs)
• Two papers:
  • General Studies Paper I
  • General Studies Paper II (CSAT)
• Both papers are of 200 marks each.
• Negative marking: 1/3rd of marks deducted for wrong answers.
• GS Paper I marks are counted for merit.
• CSAT is qualifying (minimum 33%).

Prelims is not just a screening test — it is highly competitive. Every year, the level is conceptual and unpredictable.

Now let us understand the syllabus in detail.

2. Official UPSC Syllabus – IAS Prelims

(A) General Studies Paper I

As per UPSC notification, the syllabus is:

Current events of national and international importance.
History of India and Indian National Movement.
Indian and World Geography – Physical, Social, Economic Geography of India and the World.
Indian Polity and Governance – Constitution, Political System, Panchayati Raj, Public Policy, Rights Issues, etc.
Economic and Social Development – Sustainable Development, Poverty, Inclusion, Demographics, Social Sector Initiatives, etc.
General issues on Environmental Ecology, Biodiversity and Climate Change – that do not require subject specialization.
General Science.

Let’s break this down subject-wise.

3. Detailed Syllabus of GS Paper I

3.1 Current Affairs

Official Wording:

Current events of national and international importance.

What UPSC Actually Asks:

• Government schemes
• International organizations
• Reports and indices
• Important Supreme Court judgments
• Science & tech developments
• Environmental conventions
• Budget and Economic Survey highlights

Important Areas:

• Union Budget & Economic Survey
• International relations developments
• Government initiatives
• Climate agreements
• Space missions
• Awards and appointments (selective)

Preparation Strategy:

1. Read one standard newspaper (The Hindu or Indian Express).
2. Follow PIB selectively.
3. Monthly current affairs compilation.
4. Revise at least 3–4 times before exam.

Common Mistake:

• Studying current affairs in isolation without linking to static subjects.

3.2 History of India & Indian National Movement

Official Wording:

History of India and Indian National Movement.

Important Areas:

• Ancient India (Buddhism, Jainism, Mauryan, Gupta period)
• Medieval India (Delhi Sultanate, Mughals, Bhakti-Sufi)
• Modern India (most important)
  • Revolt of 1857
  • INC sessions
  • Gandhian movements
  • Revolutionary movements
  • Governor-Generals
• Art & Culture
  • Temple architecture
  • Classical dances
  • Buddhism & Jainism
  • UNESCO sites

Frequently Asked:

• Moderate vs Extremist phase
• Constitutional developments before 1947
• Socio-religious reform movements
• Buddhism & Jainism concepts

Step-by-Step Preparation:

1. Start with NCERTs (Class 6–12).
2. Modern India – Spectrum book.
3. Art & Culture – Nitin Singhania (selectively).
4. Make timelines for Modern India.
5. Practice previous year questions (very important).

Common Mistake:

• Ignoring Art & Culture thinking it is minor. UPSC asks conceptual questions here.

3.3 Indian and World Geography

Official Wording:

Indian and World Geography – Physical, Social, Economic Geography of India and the World.

Important Areas:

Physical Geography:

• Earth structure
• Volcanoes & earthquakes
• Ocean currents
• Winds & monsoons
• Climate types

Indian Geography:

• Rivers
• Agriculture patterns
• Soil types
• Mineral distribution
• Industries

World Geography:

• Important straits, canals
• Locations in news
• Climatic regions

Preparation Strategy:

1. NCERT Class 6–12 (must).
2. Use an atlas daily.
3. Focus on maps.
4. Link geography with current affairs (cyclones, El Niño).

Common Mistake:

• Memorizing without understanding concepts.
• Ignoring map practice.

3.4 Indian Polity and Governance

Official Wording:

Indian Polity and Governance – Constitution, Political System, Panchayati Raj, Public Policy, Rights Issues, etc.

This is one of the most scoring subjects.

Important Areas:

• Constitution features
• Fundamental Rights & Duties
• DPSP
• Parliament & State Legislature
• President, PM, Governor
• Supreme Court & Judicial Review
• Constitutional & Non-Constitutional Bodies
• Amendments

Frequently Asked:

• Articles of Constitution (concept-based)
• Comparison between bodies
• Emergency provisions
• Federalism

Preparation Strategy:

1. Read Laxmikanth thoroughly.
2. Revise multiple times.
3. Practice MCQs.
4. Make short notes of important Articles.

Common Mistake:

• Rote learning articles without understanding concepts.

3.5 Economic and Social Development

Official Wording:

Economic and Social Development – Sustainable Development, Poverty, Inclusion, Demographics, Social Sector Initiatives, etc.

Important Areas:

• GDP, Inflation, Repo rate
• Monetary & Fiscal policy
• Budget basics
• Poverty & unemployment
• Government schemes
• Banking system
• Economic Survey concepts

Preparation Strategy:

1. NCERT (Class 11 & 12 basics).
2. Follow budget summary.
3. Understand terms — not just definitions.
4. Link economy with current affairs.

Common Mistake:

• Fear of economy and skipping basics.

3.6 Environment and Ecology

Official Wording:

General issues on Environmental Ecology, Biodiversity and Climate Change – that do not require subject specialization.

Important Areas:

• Biodiversity hotspots
• National parks
• IUCN status
• Climate change agreements
• Environmental conventions
• Ecology basics (food chain, ecosystem)

Preparation Strategy:

1. NCERT Biology (Class 12 – Ecology chapters).
2. Current affairs integration.
3. Revise species in news.

Common Mistake:

• Ignoring environment thinking it is science-based. It is highly current-based.

3.7 General Science

Official Wording:

General Science.

Important Areas:

• Basic Physics concepts
• Chemistry basics
• Biology fundamentals
• Science in news (vaccines, AI, space)

Focus on conceptual understanding, not advanced science.

4. CSAT (General Studies Paper II)

Official Wording:

Comprehension;
Interpersonal skills including communication skills;
Logical reasoning and analytical ability;
Decision-making and problem-solving;
General mental ability;
Basic numeracy (Class X level);
Data interpretation (Class X level).

CSAT is qualifying but many aspirants fail here.

4.1 Comprehension

• Reading passages
• Inference-based questions
• Tone and theme

Practice daily reading.

4.2 Logical Reasoning & Analytical Ability

• Seating arrangement
• Syllogism
• Blood relations
• Coding-decoding

4.3 Basic Numeracy

• Percentages
• Ratio & proportion
• Time & work
• Speed & distance
• Averages

4.4 Data Interpretation

• Tables
• Graphs
• Pie charts

CSAT Preparation Strategy:

1. Attempt previous year papers first.
2. If weak in maths, practice daily 1 hour.
3. Do not ignore CSAT till last month.
4. Take at least 5 full-length mock tests.

5. How to Prepare GS Paper I – Step-by-Step Roadmap

Step 1: Build Foundation

• Complete NCERTs.
• Understand concepts.

Step 2: Standard Books

• Polity – Laxmikanth
• Modern History – Spectrum
• Economy – Basic book + current
• Geography – NCERT + Atlas
• Environment – Current + basics

Step 3: Solve Previous Year Questions

• Analyze trends.
• Understand UPSC mindset.

Step 4: Mock Tests

• Minimum 25–30 full-length tests.
• Analyze mistakes deeply.

Step 5: Revision

• Revise at least 4–5 times.
• Make short notes.

6. Common Mistakes in Prelims Preparation

• Collecting too many books.
• Ignoring revision.
• Skipping CSAT.
• Not solving PYQs.
• Over-dependence on coaching material.
• Studying without time-bound practice.

7. Final Advice for Serious Aspirants

UPSC Prelims is not about reading everything. It is about:

• Understanding concepts deeply
• Revising repeatedly
• Practicing intelligently
• Staying consistent

The syllabus looks short, but its depth is vast. Treat the official syllabus as your guiding document. Every topic you study should connect back to it.

If you master the syllabus and align your preparation strictly with it, you will automatically move ahead of 70–80% of aspirants who prepare without clarity.

Remember:
Clarity of syllabus + Smart revision + PYQ analysis = Strong Prelims performance.

Prepare with discipline, not emotion. That is the real key to clearing IAS Prelims.