The Combined Defence Services (CDS) Examination is a national-level exam conducted twice a year by the Union Public Service Commission (UPSC) for recruitment of officer cadets into the Indian Armed Forces. Clearing the CDS exam allows graduates to join the Indian Military Academy (IMA), Indian Naval Academy (INA), Air Force Academy (AFA), or Officers’ Training Academy (OTA) as commissioned officers. The written test (objective papers in English, General Knowledge and Mathematics) is followed by a Services Selection Board (SSB) interview and a medical examination. Successful candidates are then trained at the respective academy to serve as officers.

Streams and Services (IMA, INA, AFA, OTA)

The CDS exam opens the door to four main training streams in the Indian Armed Forces:

• Indian Military Academy (IMA), Dehradun (Army) – The premier institution that trains officer cadets for the Indian Army. Graduates are commissioned as Lieutenants after about two years of training.
• Indian Naval Academy (INA), Ezhimala, Kerala (Navy) – Trains officer cadets for the Indian Navy. Candidates complete academic and sea training before commissioning as officers.
• Air Force Academy (AFA), Hyderabad (Air Force) – Trains cadets in flying and ground subjects for the Indian Air Force. Graduates are commissioned as Flying Officers.
• Officers’ Training Academy (OTA), Chennai (Army SSC) – Trains cadets for Short Service Commission (SSC) in the Army (both men and women). Officers receive about 49 weeks of training before commissioning.

Each academy has its own course structure and duration, but all focus on leadership, military skills, and academic subjects. Entry into these academies is through the CDS exam and subsequent SSB interview.

Eligibility Criteria

Candidates must meet strict nationality, age, educational and physical requirements for each academy. Key eligibility norms are:

• Nationality: Must be an Indian citizen, or a subject of Nepal/Bhutan, or a person of Indian origin from certain countries (with a certificate of eligibility).
• Age and Marital Status:

• • Indian Military Academy (IMA) – Only unmarried men. Born between 2 January 2002 and 1 January 2007 (19–24 years).
  • Indian Naval Academy (INA) – Only unmarried men. Born between 2 January 2002 and 1 January 2007 (19–24 years).
  • Air Force Academy (AFA) – Only unmarried men. Born between 2 January 2002 and 1 January 2006 (20–24 years). Must have Physics and Maths at 10+2 level or a BE degree.
  • Officers’ Training Academy (OTA) – Both men and women (unmarried men; unmarried women or eligible widows/divorcees). Born between 2 January 2001 and 1 January 2007 (19–25 years). (Women can apply only for OTA – they are not eligible for IMA, INA or AFA through CDS.)

• Educational Qualification:

• IMA & OTA: Bachelor’s degree (any discipline) from a recognized university. Final-year students may apply provisionally (with no backlogs).
• INA: Bachelor’s degree in Engineering.
• AFA: Bachelor’s degree with Physics and Mathematics at 10+2 level, or Bachelor of Engineering.

Candidates must also meet the physical and medical standards set by the Services Selection Board. For example, minimum height requirements apply and good hearing/vision is mandatory. Any serious medical issue or disqualification will bar entry.

Exam Pattern

The CDS selection process has two stages: a written examination followed by the SSB interview. The written exam pattern is as follows:

• Papers (Objective, OMR):

• For IMA/INA/AFA candidates: Three papers – English (2 hours, 100 marks), General Knowledge (2 hours, 100 marks), and Elementary Mathematics (2 hours, 100 marks). Total of 300 marks.
• For OTA candidates: Two papers – English (2 hours, 100 marks) and General Knowledge (2 hours, 100 marks). Total of 200 marks.

• Marking Scheme: Each correct answer carries +1 mark; each incorrect answer carries a penalty of –⅓ mark. (No penalty for unattempted questions.)
• Language: All papers are in English.
• Qualifying Marks: UPSC sets minimum qualifying marks per paper; these may vary each exam. Candidates must score above the cut-offs in each paper to be shortlisted.

After the written exam, qualified candidates are invited for the SSB interview, a five-day personality and intelligence assessment. The final merit is based on combined marks of the written exam and SSB interview.

Syllabus

The CDS syllabus covers graduate-level knowledge. Subjects are divided by paper as follows:

• English: Emphasizes basic grammar and comprehension. Topics include basic grammar rules, vocabulary (synonyms/antonyms), idioms, phrases, sentence correction, para jumbles, error spotting and reading comprehension passages.
• General Knowledge: Broad coverage of current affairs and static topics. Includes Current Events (national and international), History (Indian & World), Geography, Polity, Economy, General Science (Physics, Chemistry, Biology), and Defense-related informationprepp.in. Questions may also cover Environment, Culture, Literature, and everyday science.
• Elementary Mathematics: Standard Class X-level mathematics. Major areas are Arithmetic (numbers, percentages, profit-loss, time & work, etc.), Algebra (basic operations, simple equations, factors, HCF/LCM), Geometry (properties of shapes, congruence, similarity, circles), Trigonometry (basic identities, heights & distances), Mensuration (areas, volumes) and Statistics (data interpretation, averages).

Candidates are advised to refer to official UPSC syllabi and previous year question papers for detailed topic lists. The questions are purely objective-type (multiple choice). Thorough practice of each topic and familiarity with exam-style questions is crucial.

Application Process

Applications for CDS are made online through the UPSC website. Key steps include:

• Registration: Visit the UPSC website (upsc.gov.in) and complete the One-Time Registration (OTR) or login if already registered. Under “Examination” → “Apply Online”, select the CDS exam link.
• Part I Registration: Fill in personal details (name, DOB, address), educational qualifications, and choose the preferred academy (IMA/INA/AFA/OTA) and exam centres. Submit to generate a Registration ID and password.
• Part II Registration: Log in with the Registration ID. Fill in remaining details, upload required documents, and pay the fee.
• Documents Upload: Prepare scanned copies (in prescribed size/format) of:

• Recent passport-size photograph
• Signature (ink)
• Valid photo ID proof (Aadhaar, PAN, Passport, etc.)
• Educational certificates (degree or final year certificate)
• Caste certificate (if claiming SC/ST/OBC)
• Disability certificate (if applicable).

• Application Fee: ₹200 for general and OBC male candidates. Female, SC, ST, and disability candidates are exempt. Payment can be made online (net banking/debit/credit card) or via e-challan.
• Submission: Review the form for accuracy, submit it, and print/save the confirmation page for records.

Candidates should complete the application within the specified window and keep copies of all documents for future stages. After submission, a limited correction window may be provided by UPSC for any changes.

Important Dates

UPSC follows a regular cycle for CDS exams each year:

• Notification and Form: The official notification and application release typically happen in December (for CDS-I) and May/June (for CDS-II). For example, CDS-I 2025 notification was released on December 11, 2024, and CDS-II 2025 notification was released on May 28, 2025.
• Application Deadline: About 2–3 weeks after release. Candidates must apply online by the last date (e.g. December 31 for CDS-I 2025).
• Exam Dates: CDS-I exams are usually held in April, and CDS-II in September of the exam year. (For instance, CDS-I 2025 was on April 13, 2025, and CDS-II 2025 on September 14, 2025.)
• SSB Dates: SSB interviews are conducted in phases starting a few weeks after results of the written exam. Exact dates depend on the academy and the candidate’s roll number.
• Result & Merit List: Final results (merit lists by academy) are typically declared a few months after the exam, once SSB and medical exams are completed.

Candidates should regularly check the UPSC website and reputable news portals for official schedule updates. The above timeline is a general guide; exact dates can vary each year.

Admit Card & Exam Centers

Hall tickets (admit cards) are issued online by UPSC roughly 10–20 days before the exam date. For example, UPSC released CDS-I 2025 admit cards on April 3 for the April 13 exam. To download the admit card, candidates should:

• Log in to the UPSC portal (upsconline.nic.in) with their Registration ID and date of birth.
• Go to “Admit Card” under the “Examinations” tab and click the CDS link.
• Download and print the admit card.

The admit card specifies the candidate’s exam city and center. Exams are held at various centers nationwide (chosen by candidates during application). On exam day, candidates must carry: the printed admit card and a valid photo ID (Aadhaar, PAN, Driving Licence, etc.). No entry is allowed without these. Candidates should also check the exam date, shift timings, and reporting instructions mentioned on the admit card.

Selection Process

The CDS selection process combines the written exam, SSB interview, and medical tests:

1. Written Examination: Objective papers as described above. UPSC shortlists candidates based on cut-off scores.
2. SSB Interview: Qualifying candidates undergo a rigorous five-day interview at SSB centers. This two-stage process includes:

• Stage I: Officer Intelligence Rating (OIR) tests and Picture Perception & Description Test (PPDT). Those who clear Stage I are recommended for Stage II.
• Stage II: Psychological tests (Thematic Apperception Test, Word Association Test, Situation Reaction Test, etc.), Group Testing Officer (GTO) tasks (outdoor group exercises), and a personal interview by an interviewing officer. Candidates are assessed on “Officer Like Qualities” (leadership, teamwork, initiative, etc.).

1. Medical Examination: Candidates recommended by SSB undergo a thorough medical exam by Armed Forces medical boards. Strict standards are applied – for example, good binocular vision, normal cardiovascular and musculoskeletal health, and no chronic illness. Any disqualification here can remove a candidate from final merit.
2. Final Merit List: UPSC combines marks from the written exam and SSB (out of a total of 900 in SSB) to prepare academy-wise merit lists. Only those who meet both exam and medical criteria are finally selected for training.

Each academy announces its own merit list and subsequent joining instructions. The entire process is competitive; only a small percentage of aspirants clear all stages each year.

Tips for Preparation

Effective CDS preparation involves a strategic approach and consistent practice. Key tips include:

• Understand the Exam Thoroughly: Familiarize yourself with the detailed exam pattern and syllabus. Knowing the weight of each section helps allocate study time wisely.
• Structured Study Plan: Make a study schedule covering all subjects. Focus on fundamentals first (basic grammar rules, math formulas, core current affairs) before tackling advanced topics. Give extra time to weaker areas.
• Practice with Previous Papers: Solve past CDS papers and mock tests under timed conditions. This builds speed and accuracy. Regular practice identifies weak topics and helps improve your question-solving strategy. Review mistakes carefully.
• Regular Revision: Keep concise notes for quick revision. Regularly revisit important formulas, grammar rules, and facts. Flashcards or summary sheets can help for quick recall.
• Stay Updated on Current Affairs: Read newspapers and reliable news sources daily, especially on defense, national and international events. Monthly current affairs magazines or compilations can also be useful.
• Physical Fitness: Since CDS selection includes physical and medical tests, maintain good physical health. Regular exercise (running, push-ups, etc.) and a healthy diet will help clear physical standards.
• SSB Preparation: Learn about the SSB process and practice communication and personality development. Participate in group discussions and mock interviews. Strengthening soft skills (leadership, confidence, clear speech) can greatly improve SSB performance.
• Stay Motivated and Confident: Keep a positive mindset. Believe in your preparation, and manage stress through breaks and healthy routines. Consistency and discipline are key – avoid cramming at the last minute.
• Seek Guidance if Needed: Join study groups or coaching if that helps. Learning from mentors or peers can clarify doubts and provide practice feedback.

By combining academic preparation with self-assessment and discipline, candidates can maximize their chances of success in the CDS exam.