IAS Syllabus
UPSC 2020 syllabus [UPSC Civil Services Prelims and Mains] has been released along with the official notification for the Civil Service Exam on 12th February 2020.

The IAS syllabus can be found at the UPSC official website – https://upsc.gov.in/ or scroll down to download the UPSC syllabus pdf for both Prelims and Mains. 

There is a common UPSC syllabus pattern for services such as the Indian Administrative Service, Indian Foreign Service, Indian Police Service, Indian Revenue Service (Customs and Central Excise) to name a few. However, different stages of the IAS exam have different syllabi. The UPSC Prelims syllabus focuses on general and societal awareness which is tested by objective-type (MCQ) questions. The UPSC Mains syllabus is much more comprehensive as this stage comprises nine theory papers.

The Civil services exam is conducted in three phases:

Phase 1: Civil Services (Preliminary) Examination (Objective Type)

Phase 2: Civil Services (Mains) Examination (Descriptive Type)

Phase 3: Personal Interview (Personality Test)


Phase 1: UPSC Prelims Exam

The UPSC Civil Services Prelims Examination is composed of two components:

1) General Studies

Paper    Subjects                                Total     Time                Duration
I           General Studies (GS)          200       2 hours    (9:30 AM to 11:30 AM)                                                                                                                                                      II                                        CSAT                                    200       2 hours     (2:30 PM to 4:30 PM)
2) Civil Services Aptitude Test (CSAT)


Broadly, the UPSC Civil Services (Preliminary) Examination consists of two papers of objective type, each of 200 marks (hence totaling 400 marks) and of two hours duration. To qualify for the Civil Services Mains, a candidate must attempt both the papers.
Further, the UPSC General Studies (GS) paper consists of 100 questions, while the CSAT paper consists of 80 questions. Both papers have negative marks for wrong answers marked to the tune of 1/3rd of the total marks assigned to that question.
To further illustrate this, each correctly answered GS question will be awarded 2 marks. So, 0.66 marks would be deducted from the total for every question that is wrongly marked.
Similarly, in the CSAT paper, since we have 80 questions for 200 marks, correctly answered CSAT question would attract 2.5 marks each, while every wrongly marked question would attract a penalty of 0.833 for each such wrong answer, which will be deducted from the total.
Questions that are not attempted will not attract any negative marks.
The two papers of the IAS prelims are discussed in detail below:

General Studies (Generally conducted between 9:30 AM to 11:30 AM)
The General Studies test is the first paper of the preliminary examination. This test is intended to test the general awareness of a candidate in a wide range of subjects that include: Indian Polity, Geography, History, Indian Economy, Science and Technology, Environment and Ecology, International Relations and associated UPSC current affairs.

Civil Services Aptitude Test (CSAT) (Generally conducted between 2:30 PM to 04:30 PM)
This UPSC Prelims syllabus for CSAT intends to assess the aptitude of the candidate in solving ‘Reasoning and Analytical’ questions, apart from ‘Reading Comprehension’ and the occasionally asked ‘Decision Making’ questions.
The ‘Decision Making’ based questions are generally exempt from negative marks.
The preliminary examination is only meant for screening a candidate for the subsequent stages of the exam.
The marks obtained in the Prelims will not be added up while arriving at the final rank list.
UPSC Prelims Syllabus
Syllabus for GS Paper (Prelims Paper I)
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 specialisation.
General Science
Syllabus for CSAT Paper (Prelims Paper II)
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, etc.) (Class X level), Data interpretation (charts, graphs, tables, data sufficiency etc. – Class X level)
Phase 2: UPSC Mains Exam (1750 Marks)

The Mains examination constitutes the 2nd phase of the Civil Services Examination. Only after successfully qualifying in the prelims exam would the candidates be allowed to write the IAS Mains.
The Mains exam tests the candidate’s academic talent in depth and his/her ability to present his/her understanding according to the requirements of the question in a time-bound manner.
The UPSC Mains exam consists of 9 papers, out of which two are qualifying papers of 300 marks each.
The two qualifying papers are:
Any Indian Language
English Language Paper
The papers on Essay, General Studies and Optional Subject of only such candidates who attain 25% marks in both the language papers as a minimum qualifying standard in these qualifying papers, will be taken cognizance of, for evaluation.

In case a candidate does not qualify in these language papers, then the marks obtained by such candidates will not be considered or counted.

Structure of the language papers:

The types of questions asked are –

Essay – 100 marks
Reading comprehension – 60 marks
Precis Writing – 60 marks
English to compulsory language (e.g. Hindi) – 20 marks
Compulsory language to English – 20 marks
Grammar and basic language usage – 40 marks
The rest of the seven papers can be written in any of the languages mentioned under the Eighth Schedule of the Constitution of India or in English.

UPSC Mains Syllabus
Paper             Subject                                                                                      Marks
Paper – I     Essay (can be written in the medium of the candidate’s choice)    250 Paper – II   General Studies – I (Indian  Culture, History & Geography )           250      Paper – III  General Studies – II (Constitution, Polity, Social Justice & I R)       250 Paper – IV  General Studies – III (Technology,Economic, Security &D M)        250      Paper – V   General Studies – IV (Ethics, Integrity & Aptitude)                      250 Paper – VI   Optional Subject – Paper I                                                         250 Paper – VII   Optional Subject – Paper II                                                        250
Please check the detailed 

The UPSC Mains syllabus gives a list of 48 Optional Subjects which include Literature of different languages. Candidates need to choose any one of the ‘Optional Subjects’