Combined Defence Services Examination
UPSC examination for recruitment to the Indian Military Academy, Indian Naval Academy, Air Force Academy and Officers Training Academy.
Eligibility
Overview
CDS, conducted twice a year by UPSC, is the entry route for graduates into the Indian Military Academy (IMA), Indian Naval Academy (INA), Air Force Academy (AFA), and the Officers' Training Academy (OTA), leading to a commission as an officer.
Conducting authority
Union Public Service Commission (UPSC), with the SSB interview run by the Ministry of Defence.
Nationality
Indian citizen, permanently settled in India (subject to the specific conditions for each academy in the notification).
Educational qualification
| Academy | Qualification |
|---|---|
| IMA / OTA | Bachelor's degree (any stream) |
| Air Force Academy (AFA) | Bachelor's degree with Physics and Mathematics at 10+2 level, or an engineering degree |
| Naval Academy (INA) | Bachelor's degree in engineering |
Final-year students may apply provisionally.
Age limit
| Academy | Age limit |
|---|---|
| IMA / INA | 19-24 years |
| Air Force Academy (AFA) | 20-24 years |
| Officers' Training Academy (OTA) | 19-25 years |
Number of attempts
Not capped by a fixed attempt count — governed by the age window for the academy applied to, so eligibility is really a function of age rather than number of prior attempts.
Note on gender
Both men and women may apply; women candidates are eligible only for the Officers' Training Academy (OTA) stream.
Exam Pattern
Stages
- Written Examination (objective, single day)
- SSB Interview
Written exam pattern
| Stream | Papers | Total marks |
|---|---|---|
| IMA / INA / AFA | English, General Knowledge, Elementary Mathematics | 300 |
| OTA | English, General Knowledge | 200 |
OTA leads to a Short Service Commission rather than the permanent-commission academies, which is why it has no Mathematics paper.
SSB Interview
Candidates who clear the written stage attend a multi-day SSB assessment of officer-like qualities, similar in structure to the NDA's SSB process.
Marking scheme and negative marking
Negative marking applies to wrong answers in the objective written papers, as specified in that cycle's notification.
Selection process
Final merit and academy allocation is based on the combined written exam and SSB scores, with medical fitness as a further requirement before joining.
Preparation Guide
How to prepare
Because the Mathematics paper (for IMA/INA/AFA) is set at a comparatively accessible Class 10 level, accuracy and speed under time pressure matter more than topic difficulty — this is a paper where careless errors cost more than knowledge gaps. English and General Knowledge reward the same steady, cumulative reading habit that benefits any current-affairs-heavy exam on this list.
Important dates
CDS runs two exam cycles a year (CDS I and CDS II), each with its own notification and exam date — confirm current-cycle dates against the official notification.
Frequently asked questions
- Can women apply to IMA/INA/AFA? No — women candidates are eligible only for OTA.
- Is Mathematics compulsory for OTA candidates? No — OTA has only English and General Knowledge papers.
Official website
upsc.gov.in — confirm the current CDS I/II notification, academy-wise vacancies and exam date here.