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IAS Exam Pattern 2021, Syllabus, Marking Scheme and Compulsory Papers

Updated On -

Jan 7, 2021

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Nikkil Visha

Exams Prep Master

UPSC has announced IAS 2020 Prelims Result, conducted on October 4, at its official website – on October 23, 2020. The result is published as a PDF file having the roll numbers of qualified candidates. Download Result PDFThe aspirants, who have qualified the exam, need to submit their Detailed Application Form-I (DAF-I) through online by 11 November 2020 to appear for the IAS Main Exam 2020. 

IAS Exam Pattern talks about the distribution of questions, marking schemes, sectional weightage, and duration. The brief for all three stages of IAS are:

  • IAS Preliminary Exam
  • IAS Main Exam
  • IAS Personality Test

Latest Update:

28 October 2020: The DAF for IAS Mains 2020 has been released on the official website. Read more here

27 October 2020: The list of names of qualifiers for IAS Prelims 2020 has been released. Read more here

24 October 2020: UPSC has declared the UPSC IAS Prelims 2020 Result.

16 October 2020: IAS Prelims Toppers 2020 marks have been published by the UPSC.

16 October 2020: IAS 2019 mark sheet has been published by UPSC.

12 October 2020: In Supreme Court, a petition was filed for attempting an additional attempt the UPSC 2021 exam. 

Get FREE IAS 2021 Mock Tests, Sectional Quiz, Previous Years Papers. Click Here

Overview of UPSC IAS 2020 Exam Pattern

Name of the exam

Civil Services Exam- IAS

Conducting authority

Union Public Service Commission

Mode of Exam


Number of Stages

Prelims exam
Mains exam

Number of papers

Prelims: 2
Mains: 9

Prelims marking scheme

Paper 1: +2 marks

Paper 2: +2.5 marks

Negative marking: One-third of marks allotted to each question


Prelims: 2 hours (Each paper)

Mains: 3 hours (Each paper)

Type of questions

Prelims: Objective type

Mains: Subjective type


1000 (Tentative)

IAS Prelim Exam Pattern

IAS Exam Pattern for Prelims

  • The Prelims stage of IAS consists of 2 compulsory papers- General Ability Test (GAT) and the Civil Service Aptitude Test (CSAT). This will test the analytical skills of the candidates.
  • All questions are objective in nature. Candidates are required to choose any one of the 4 answer choices given for each question.
  • Questions are set in both English and Hindi Language. However, questions relating to the English Language Comprehension skills of the class 10th level is tested through a passage from English language only without providing Hindi translation thereof in the question paper.
  • IAS Prelims is a qualifying exam. Candidates have to get a minimum of 33 % to be qualified for the Mains. 
  • The number of candidates to be admitted to Mains is about twelve to thirteen times the total an approximate number of vacancies to be filled in the year through this examination

Check IAS Syllabus

Here are the highlights of IAS Exam Pattern for Prelims:

IAS Exam Pattern for Prelims
Exam Mode Offline
Number of Papers 2- General Studies and Civil Service Aptitude Test (CSAT)
Number of Questions Paper 1- 100; Paper 2- 80
Question Paper Type Multiple Choice Questions 
IAS Prelims Total Marks 400
Nature of Exam Qualifying
Exam Duration 2 hours each, +20 minutes for blind students
Exam Language English and Hindi

IAS Marking Scheme for Prelims

  • Each question in the General Studies paper carries 2 marks.
  • Each question in the Civil Service Aptitude Test paper carries 2.5 marks.
  • For each question for which a wrong answer has been given by the candidate, one-third (0.33) of the marks assigned to that question will be deducted as penalty.
  • If a candidate gives more than one answer, it will be treated as a wrong answer even if one of the given answers happens to be correct and the penalty will be the same as mentioned above for that question.
  • If a question is left blank, i.e. no answer is given by the candidate, there will be no penalty for that question.
  • Paper-II (CSAT) in the IAS exam is of qualifying nature and candidates should score a minimum of 33 percent in this paper to qualify for the next stage of the IAS exam i.e. the Mains.

Check IAS Cutoff

Negative Marking

The aspirants may get negative marks in the IAS Prelims Exam. More specifically, in the case of three incorrect answers, the aspirants will get a deduction of 1 mark. That is, the aspirants will get 1/3 mark deduction for every incorrect answer. On the other hand, there will be no deduction if the candidates will leave blank any of the answers. Read about IAS Preparation Tips

IAS Main Exam Pattern

Go through the practice of previous years’ papers of IAS Exam free of cost

IAS Exam Pattern for Mains

  • IAS Mains is also an offline exam. Each paper will carry 250 marks. 
  • Each paper is of 3 hours. 30 minutes are given extra to blind students.
  • The exam will contain 9 papers. A candidate will be tested on the basis of their knowledge and understanding of the subject
  • Questions will be subjective in nature. They will be given in both Hindi and English language.
  • IAS Mains is further divided into two types – Qualifying Exam and Merit Exam. It is compulsory to appear in both.

Go through the practice of previous years’ papers of IAS Exam free of cost

Qualifying Papers- 

  1. Paper A: (One of the Indian Languages to be selected from the ones included in the 8th Schedule of the Constitution – 300 Marks)
  2. Paper B: English – 300 Marks

Merit Exams- Candidates will have to score a minimum percentage in the qualifying exam to qualify for the exam. The question papers are prepared to test the intellectual and interpersonal skills of the candidate. The essay type questions will test the student's understanding of the subject and the concept. The students will be tested on the strength of an Indian Language. There would be two optional papers that the candidates would have to select. Check IAS Interview Preparation tips

The following table will enrich the candidates for the compulsory papers, the marks allotted in which would be added to calculate Merit:

Paper Title of the Paper Marks Allotted 
Paper 1 Essay writing 250 Marks
Paper 2 General Studies–I (Indian Heritage and Culture, History, and Geography of the World and Society) 250 Marks
Paper 3 General Studies –II (Governance, Constitution, Polity, Social Justice and International relations) 250 Marks
Paper 4 General Studies –III  (Technology, Economic Development, Bio‐diversity, Environment, Security and Disaster Management) 250 Marks
Paper 5 General Studies –IV (Ethics, Integrity, and Aptitude) 250 Marks
Paper 6 Optional Subject – Paper 1 250 Marks
Paper 7 Optional Subject – Paper 2 250 Marks
-   Sub Total in the written Test   1750 Marks
-   Personal Interview   275 Marks
- Grand Total ( for merit calculation) 2025 Marks

Check IAS Exam Cut off

IAS Marking Scheme for Mains

  • The total marks of the Mains Examination are 1750 marks.
  • Candidates will be graded on the basis of opinion, Content flow, understanding the problems/ situation, offering feasible solutions/strategies, presentation, and language
  • Candidates can choose two optional papers on which they will be questioned.

List of Optional Subjects

List of Optional Subjects in IAS Mains


Anthropology Chemistry
Geography History Political Science & International Relations
Commerce & Accountancy Economics Management
Mathematics Mechanical Engineering Psychology
Public Administration Sociology Electrical Engineering
Physics Zoology Medical Science
Animal Husbandry& Veterinary Science Botany Civil Engineering
Geology Law Philosophy
Statistics - -

Check IAS Mock test and practice papers

IAS Personality Test

IAS Exam Pattern for Personality Test

  • All candidates qualifying the Mains examination will proceed towards the Personality Test.
  • This would include the Psychometric Test, Assessment Test as well as the Personal Interview.
  • The objective of the interview is to assess the personal suitability of the candidate for a career in public service by a Board of competent and unbiased observers. The candidate will be asked questions on matters of general interest. 
  • The test is intended to judge the mental caliber of a candidate. 
  • In broad terms, this is really an assessment of not only his intellectual qualities but also social traits and his interest in current affairs. 
  • Some of the qualities to be judged are mental alertness, critical powers of assimilation, clear and logical exposition, the balance of judgment, variety, and depth of interest, ability for social cohesion and leadership, intellectual and moral integrity.
  • This test will be conducted in the language of choice. 
  • The interview will be graded for 275 marks. The total marks of IAS are 2025 marks 
  • Candidates will be ranked on the basis of the grand total and called for the final interview.

Check IAS Selection Procedure

IAS Syllabus

IAS Syllabus 2020

Preliminary Round

Paper 1 – General Awareness

This paper will test the candidates’ knowledge and passion for the country. The questions will be from various aspects like history, geography, economy, etc pertaining to the country. Some of the important topics include:

  • Events and Happening of National Importance
  • Impact of Geography in the country
  • Governance and Constitutional Structure
  • Current Issues faced by the country
  • Economic and Social Development
  • Research and Development
  • Scientific Developments

Read IAS Selection Process

Paper 2 – English & General Aptitude

The command of English is mandatory in the field of Public Service and candidates have to score a minimum of 33 % to qualify for the exam. The aptitude of a person determines his ability to solve complex problems, time management, and agility. The important areas to practice for IAS Exam include

  • Logical Reasoning
  • Problem Solving Capacity
  • Interpersonal Skills
  • Numerical Ability
  • Analytical Skills
  • Comprehension
  • Antonyms  / Synonyms

Read complete IAS Syllabus

Mains Round

Paper 3 – Essay Writing

Candidates can write the essay on the topic of their choice

Paper 4 – General Studies I

This paper will contain questions relating to ancient India pertaining to History, Geography, Heritage, Culture, etc. Some of the topics include

  • History of India – Ancient and Modern
  • Significant changes in Architecture, Literature, etc.
  • Geographical Significance
  • Notable events in World History
  • Diversity
  • Globalization

Paper 5 – General Studies II

This paper will contain questions about the reforms in Indian Governance post-Independence. The topics include

  • Constitution of India
  • Constitutional Analysis of the world
  • Parliament and Legislatures
  • Key issues faced by the nation and solutions
  • Welfare Schemes by the Government
  • Department and Structures in Government
IAS Sample Papers, IAS Practice Papers

Paper 6 – General Studies III

This paper will contain questions about Modern India and recent Key developments. The topics include

  • Indian Economy
  • Farming
  • Science
  • Research and Development
  • Information Technology
  • Environmental Studies
  • Achievements in various fields
  • Security Challenges
  • Industrial Growth
  • Infrastructural developments

Paper 7 – General Studies IV

This paper will contain questions about Ethics, Integrity, and Aptitude. The topics include

  • Ethics in Public Administration
  • Emotional Intelligence
  • Behavioral Analysis
  • Functional Values

Paper 8 & 9 – Candidates can select their desired subject from the list of subjects given below

  • Agriculture
  • Animal Husbandry and Veterinary Science
  • Anthropology
  • Botany
  • Chemistry
  • Civil Engineering
  • Commerce and Accountancy
  • Economics
  • Electrical Engineering
  • Geography
  • Geology
  • Indian History
  • Law
  • Management
  • Mathematics
  • Mechanical Engineering
  • Medical Science
  • Philosophy
  • Physics
  • Political Science and International Relations
  • Psychology
  • Public Administration
  • Sociology
  • Statistics
  • Zoology
Note: Candidate can also select one of the regional languages as an optional subject.

IAS Preparation Books

Read Current Affairs (Polity and Governance Part II) before appearing for IAS exam

IAS Preparation Books

Here are some of the most recommended books for IAS Preparation. We suggest you make vital use of your time and go through these books. 

important books
Subject Book Name Author/ Publisher
 History Ancient India  RS Sharma 
 History Modern India Satish Chandra Mittal
History History Of Modern India Bipan Chandra
Polity The Constitution of India   PM Bakshi
Ethics Ethics, Aptitude and Integrity for Civil Services Mail Examination Subba Rao and P.N. Roy Chaudary
Economy Indian Economy  Mishra and Puri
Environment Environmental Studies: From Crisis to Cure Rajagopalan
Environment Environment for Civil Services Prelims and Mains Khullar
Science and Technology Science and Technology in India TMH
English High School English Grammar and Composition  Wren and Martin
General Studies IAS Mains Exam General Studies (IAS Mains Exam General Studies) Ashish Bharti (IPS)


2. Certificate Physical Geography: G C Leong

3. World Atlas


Check IAS Preparation Tips


Ques. What are the best books for UPSC civil services prelims?

Ans. The following are the best books for UPSC Prelims-

  • Ancient India - RS Sharma
  • Modern India- Satish Chandra Mittal
  • History Of Modern India- Bipan Chandra
  • The Constitution of India - PM Bakshi
  • Indian Economy Mishra and Puri
  • Environmental Studies: From Crisis to Cure- Rajagopalan
  • Environment for Civil Services Prelims and Mains- Khullar
  • Science and Technology in India- TMH
  • High School English Grammar and Composition- Wren and Martin

Ques. What is the IAS Exam pattern of the UPSC main?

Ans. There are 2 compulsory language papers, 4 general studies papers, and 2 optional papers in the UPSC Mains. The total marks for all the exams are 1750 and each paper has 3 hours’ time duration. You can check the details of the main exam here.

Ques. Which subjects are compulsory and optional in UPSC?

Ans. English comprehension, regional language papers, and the four general studies papers are all compulsory. You can select a subject of your choice for the optional papers in UPSC. History, geography, public administration, sociology, mechanical engineering, and many other similar subjects are there for you to choose for the optional paper.

Ques. Is mathematics a good optional subject for UPSC?

Ans. Maths is very scoring for UPSC and you do not have to memorize anything. But on the other, it requires lots of practice and has a huge syllabus. You can learn more about mathematics optional and relevant preparation tips here.

Ques. How is geography as an optional for UPSC?

Ans. Geography is a very popular subject and chosen by many aspirants as optional paper. It overlaps to a certain extent with general studies papers too making it a smart choice. However, whether it is the best choice for you depends entirely on your preference and aptitude.

*The article might have information for the previous academic years, please refer the official website of the exam.


malay trivedi
How many essays do we have to write in UPSC Mains Paper 1

Hi Malay

You can go through our website to get the exam pattern and syllabus for IAS Exam. You will find all the details of the exams and how you can prepare for the exam.

koyena biswas
Can a candidate write different papers of Civil Service (Main) Examination in different languages?
kavita rani

Hi Koyena. Candidates can’t write mains in two languages. Whole examination can be given in one language except one out of total 9 papers. That one paper is of regional language other than English.

ibashisha mukhim
Which is the language / medium of question papers?
kavita rani

Hi Ibashisha. The mode of the exam is Hindi and English. Qualifying Papers in the IAS include Paper A (Indian Language) and Paper B (English). Other details related to the same are mentioned here.

divakar sharma
Is the Indian language Paper compulsory for candidates hailing from the States of Arunachal Pradesh, Manipur, Meghalaya, Mizoram, Nagaland and Sikkim?
kavita rani

Hi Divakar. Candidates belonging to the north-eastern states of Sikkim, Arunachal Pradesh, Meghalaya, Manipur, Mizoram and Nagaland are exempted from taking the compulsory Indian language paper.

kashish tomar
How are the Question Papers for the Civil Services (Main) Examination structured? What is the duration of each paper?
kavita rani

Hi Kasish. There are 2 compulsory language papers, 4 general studies papers, and 2 optional papers in the UPSC Mains. Check other details here.

sheetal chib
Is there any negative marking at the Civil Services (Preliminary) Examination?
kavita rani

Hi sheetal. Yes, for each wrong answer, one-third (0.33) marks assigned will be deducted as penalty. 

jitender singh
Ma'am I am a 1st year Computer science and engineering student guide me how to start the preparation for UPSC..
abdul nazir

Hi Jitender, To begin with the preparation, you must under the syllabus thoroughly. Then follow the preparation tips and strategies to score well in the UPSC exams. To understand the detailed preparation strategies for UPSC click here.

marri nanda swaroop
Sir please give me a detail information about.....the qualification required for cracking IPS exam!!!
arvind kumar

Hi Marri, you must be a graduate from any recognised university and should have attained the age of 21 years. For details visit: IAS 2020

kriya kanunga
Sir/Ma'am can you plz let us know what are the areas at which I need to be best ? I'm from commerce so which are the subjects that I should focus upon?
arvind kumar

Hi Kriya, you must focus on history, geography, political science, economics, current affairs, science, environment and all basic knowledge. For details visit: IAS EXAM

kriya kanunga
Sir I'm in FY BBA When can I give IAS exam ? Can you mention proper month?
arvind kumar

Hi Kriya, the exam is generally conducted in the month of june. you can give the exam when complete 21 years of age. For details visit: IAS EXAM

dhakane samir
Hi sir I have passed out 12th exam and I want to prepare for ias plzz tell me where should I start??
rakhisree chatterjee

Hi Dhakane, Search about IAS exam pattern and make a study plan. Make a habit of reading the newspaper daily and keep yourself updated with the current happening in the country as well outside the country. Be well versed with the syllabus and start taking notes. Practise previous years IAS question papers.

vaibhav awchar
Hi I am preparing to upsc for 2021 Last PRE exam i got about 105 marks in c sat paper but first general paper not clear Please guide me About the first general paper I am civil engineeing students and started prepration from ncert book, current affair But I can't knowledge about the book for first general paper
arvind kumar

Hi Vaibhav, for GS paper you must have a good knowledge about current affairs and have all basic knowledge of subjects history, geography, economics, political science. For more details visit: IAS EXAM

ankit kumar
Hindi literature is my optional subject. Is it right for Hindi medium student?
sachin sharma
I am in indian navy, I want to preparing for upsc, bt how did I start it, I don't understand, please guide me


Please start practicing wrting, reading about current affairs and for more details on the preparation tricks, kindly check: UPSC preparation

divakar sharma
How do you clear the UPSC exam with a top ranking in the first attempt?
kavita rani

Hi Divakar. You must be well-versed with the latest UPSC exam pattern and syllabus. Understanding the latest paper pattern is important so that you can study in the right manner. In case, you want to check the latest Syllabus for Prelims and Main, Pattern and recommended books, refer here.

kunal thakrar
I am a 3rd year engineering student and a “zero level” UPSC aspirant. I’m unsure what my next step is. How one can prepare for UPSC while studying in an engineering college?
kavita rani

Hi Kunal. The majority of the college aspirants can prepare for the IAS exam while studying in their college only because studying at a comfortable place improves the chances of clearing the exam. Work hard and stay focused as it will help you get success in your life.

mohammad huzeifa
I am a student from ECE,do I have any chances to write UPSC exam.If yes,what is the syllabus for ECE students????


The following topics can be covered:

  1. Physical Electronics
  2.  Electron Devices 
  3. Signals and Systems
  4.  Network Theory
  5.  Electromagnetic Theory
  6. Electronic Measurements and Instrumentation: ...
nripendra nayan
does physics ; chemistry; bio ; of 11th and 12th is reading necessary for upsc examination.


NCERT is required to crack the general science questions in the exams. 

puja sao
How many months of current affairs should be prepared for the IAS exam?
kavita rani

Hi Puja. You must know the latest current affairs (of at least 6 months) to give the IAS exam.

syed aqib
Can we choose English as our regional language


Yes, the students can choose English, Hindi and any other language as their regional language.