Complete UPSC Syllabus: Prelims, Mains, Interview & Optional Subjects Explained

Check the complete UPSC Syllabus 2026 for Prelims, Mains, Optional Subjects, and Interview. Download the latest IAS syllabus and start preparation.

UPSC Syllabus

Complete UPSC Syllabus: Prelims, Mains, Interview & Optional Subjects Explained

The UPSC Civil Services Examination (CSE) is one of the most competitive and prestigious examinations in India. The first step towards the preparation is to have a clear understanding of the UPSC syllabus. It is the foundation on which the smart and targeted preparation is built.

Prepare as per the UPSC CSE syllabus. It tells you exactly what UPSC expects from the candidates. When you have a good understanding of the UPSC syllabus, you can choose the right books, make a proper study plan, and save time without wasting it on unnecessary topics. A syllabus-based preparation strategy helps aspirants to stay focused and increase their chances of success. 

UPSC Prelims Syllabus

The preliminary examination is the first stage of the UPSC Civil Services Examination. It consists of two papers:

Paper

Subject

Marks

Paper I

General Studies (GS)

200 Marks

Paper II

CSAT

200 Marks

Total

Prelims

400 Marks

Only the marks of General Studies Paper I are counted for prelims merit. CSAT is qualifying in nature, and candidates must score at least 33% marks.

1. General Studies Paper I Syllabus (200 Marks)

General Studies Paper I covers a broad range of subjects and plays a crucial role in clearing the prelims.

Important topics include:

  • Current Affairs of National and International Importance
  • History of India and Indian National Movement
  • Indian and World Geography
  • Indian Polity and Governance
  • Economic and Social Development
  • Environment and Ecology
  • General Science

Students should focus on NCERT books, standard reference books, and daily UPSC current affairs to build a strong foundation.

2. UPSC CSAT Syllabus (General Studies Paper II) (200 Marks)

The CSAT paper tests aptitude and analytical skills.

Important topics include:

  • Reading Comprehension
  • Logical Reasoning
  • Analytical Ability
  • Decision Making
  • Problem Solving
  • Basic Numeracy
  • Data Interpretation

Many students underestimate CSAT because it is qualifying. However, recent UPSC trends show that the paper has become more challenging. Regular practice is necessary to clear this paper comfortably.

UPSC Mains Examination Syllabus

Candidates who qualify for the prelims appear for the mains examination. The main stage evaluates a candidate's understanding, analytical skills, and answer-writing ability.

UPSC Mains Exam Pattern and Marks

Paper

Subject

Marks

Paper A

Indian Language

300

Paper B

English

300

Essay

Essay Paper

250

GS Paper I

General Studies I

250

GS Paper II

General Studies II

250

GS Paper III

General Studies III

250

GS Paper IV

General Studies IV

250

Optional Paper I

Optional Subject

250

Optional Paper II

Optional Subject

250

Total Merit Marks

 

1750

1. Qualifying Papers

Paper A: Indian Language (300 Marks)

This paper tests language proficiency in one of the languages listed in the Eighth Schedule of the Constitution.

Topics include:

  • Essay Writing
  • Reading Comprehension
  • Grammar
  • Translation
  • Precis Writing

Paper B: English (300 Marks)

This paper checks a candidate's basic English language skills.

Topics include:

  • Essay Writing
  • Comprehension
  • Grammar
  • Precis Writing
  • Vocabulary

Although these papers are qualifying in nature, candidates must pass them to have their other papers evaluated.

2. UPSC Mains GS Paper I Syllabus (250 Marks)

This paper focuses on history, culture, society, and geography.

Important topics include:

  • Indian Heritage and Culture
  • Ancient and Modern Indian History
  • World History
  • Indian Society
  • Geography of India and the World

This paper requires conceptual clarity and a strong understanding of social and historical developments.

3. UPSC Mains GS Paper II Syllabus (250 Marks)

This paper covers governance and political systems.

Important topics include:

  • Indian Constitution
  • Governance
  • Parliament and State Legislatures
  • Judiciary
  • Social Justice
  • International Relations

Current affairs play a major role in this paper.

4. UPSC Mains GS Paper III Syllabus (250 Marks)

This paper focuses on development and security-related issues.

Topics include:

  • Indian Economy
  • Agriculture
  • Science and Technology
  • Environment and Biodiversity
  • Disaster Management
  • Internal Security

Students should regularly connect current affairs with these topics.

5. UPSC Mains GS Paper IV Syllabus (250 Marks)

This is the Ethics, Integrity, and Aptitude paper.

Important topics include:

  • Ethics and Human Interface
  • Integrity
  • Aptitude
  • Emotional Intelligence
  • Public Service Values
  • Ethical Case Studies

This paper evaluates a candidate's ethical thinking and decision-making ability.

6. UPSC Essay Paper Syllabus (250 Marks)

The essay paper tests a candidate's ability to express ideas clearly and logically.

Topics may come from:

  • Governance
  • Economy
  • Education
  • Social Issues
  • Environment
  • Technology
  • International Relations

Good essay writing requires regular practice and structured thinking.

7. UPSC Optional Subject Syllabus (500 Marks)

The UPSC optional subject is one of the most important parts of the Civil Services Examination (Mains). Candidates should select any one subject as per their interest, educational background, and knowledge of the subject. The optional subject will have 2 papers, and each paper will carry 250 marks, with a total of 500 marks.

Optional subjects have a huge weightage in the final merit list, so choosing the right optional subject and preparing well for it can improve your chances of getting a better rank in UPSC. Sociology, anthropology, geography, history, political science, public administration and psychology are popular optional subjects. For long-term preparation, it is usually best to do it on a subject that matches your interests and strengths. 

Marks Distribution:

  • Optional Subject Paper I – 250 Marks
  • Optional Subject Paper II – 250 Marks
  • Total Optional Subject Marks – 500 Marks

UPSC CSE Interview

The UPSC Interview (Personality Test) is the final stage of the UPSC Civil Services Examination.

Stage

Marks

Personality Test (Interview)

275 Marks

How Vedanta IAS Academy Helps You Cover the Complete UPSC Syllabus

Completing the entire IAS UPSC syllabus can be a daunting task. At Vedanta IAS Academy, we assist aspirants in streamlining this process by providing expert guidance and structured learning. 

1. Expert Faculty Guidance: Our expert mentors make it easy & simple to understand each topic.

2. Structured Study Plans: Students are provided with a clear roadmap on how to prepare for prelims, mains and interviews.

3. Prelims + Mains Integrated Preparation: We make sure that students study for both stages at the same time.

4. Optional Subject Support: Guidance and mentorship for optional subject selection and preparation.

5. Test Series and Mentorship: Regular mock tests, answer-writing practice and personalized feedback help students to improve constantly.

6. Current Affairs Coverage: Our new current affairs programmes help students link dry subjects with current developments.

Frequently Asked Questions (FAQ)

Q1. Is the UPSC Prelims and Mains syllabus the same?

Ans. No. The Prelims has objective-type questions, whereas the Mains has descriptive and analytical answers.

Q2. How many subjects are there in the UPSC syllabus?

Ans. The UPSC syllabus comprises of history, geography, polity, economy, environment, science, ethics, essays, current affairs and optional subjects.

Q3. Which is the toughest part of UPSC syllabus?

Ans. Answer will be different for each student. Many aspirants have problems in ethics, optional subjects or current affairs.

Q4. Does the UPSC syllabus change every year?

Ans. The basic syllabus is almost the same, but UPSC can change the focus as per the current developments.

Q5. How long does it take to complete the UPSC syllabus?

Ans. For most of the aspirants, it takes around 10–18 months of dedicated preparation to cover the entire syllabus.

Q6. Which optional subject is best for UPSC?

Ans. The best optional subject is no optional subject. The best choice depends on your interest, background and preparation strategy.