As you want to get the exam pattern for the IAS in preliminary & mains so here it is for you:

Scheme of CS (Preliminary) Examination

The Preliminary Examination consists of two papers of objective type (multiple-choice questions) carrying a maximum of 400 marks.
The Question Papers (Test Booklets) are set in English & Hindi

General Studies Paper - I 200 Marks
General Studies Paper - II 200 Marks

Scheme - CS (Main)

Paper-I
One of the Indian Languages to be selected by the candidate from the 18 languages included in the VIIIth Schedule to the Constitution (Qualifying Paper)
300 Marks

Paper-II English (Qualifying Paper) 300 Marks

Paper-III Essay 200 Marks

Papers IV & V General Studies (300 Marks for each paper) 600 Marks

Papers VI, VII, VIII & IX

Any two subjects (each having 2 papers) to be selected from the prescribed optional subjects (300 marks for each paper)
1200 Marks

Total Marks for Written Examination 2000 Marks

Interview Test 300 Marks

Grand Total 2300 Marks

List of Optional Subjects - CS (Main) - (Total 25):
Agriculture
Management
Animal Husbandry & Vetinary Science
Mathematics
Anthropology
Mechanical Engineering
Botany
Medical Science
Chemistry
Philosophy
Civil Engineering
Physics
Commerce & Accountancy
Political Science & International Relations
Economics Psychology
Electrical Engineering
Public Administration
Geography
Sociology
Geology
Statistics
Indian History
Zoology
Law

List of Optional Subjects (Literature) - CS (Main) - (Total 26)
Arabic
Gujarati
Manipuri
Sanskrit
Assamese
Hindi
Nepali
Sindhi
Bengali
Kannada
Oriya
Tamil
Chinese
Kashmiri
Pali
Telugu
English
Konkani
Persian
Urdu
French
Marathi
Punjabi
German
Malayalam
Russian

Contact Details:
Union Public Service Commission
UPSC,
Man Singh Road Area,
New Delhi,
Delhi 110069
India

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