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CDS

Combined Defence Services Examination

Graduate-level entry to IMA, Naval Academy, Air Force Academy and OTA. UPSC written followed by SSB.

Who it's for

Graduates entering IMA, INA, AFA or OTA

Eligibility
  • Indian citizen
  • Bachelor's degree
  • Age ~19–25 (varies by academy)
Selection stages
  1. UPSC written (English, GK, Maths)
  2. SSB interview
  3. Medical
📊 Syllabus & topic weightage

What the CDS written exam actually asks, topic by topic — so you study the heavy areas first.

English

120 questions · 100 marks · 120 min · ≈0.83 marks each · 1/3 negative marking
Official syllabus areas (no reliable per-topic counts).
Spotting ErrorsSynonyms & AntonymsReading ComprehensionOrdering of Words & SentencesSentence ImprovementCloze Test & Fill in the blanksIdioms & Phrases

General Knowledge

120 questions · 100 marks · 120 min · ≈0.83 marks each · 1/3 negative marking
Official syllabus areas (no reliable per-topic counts).
HistoryGeographyPolityEconomicsGeneral Science (Physics, Chemistry, Biology)Current AffairsDefence & Awards

Elementary Mathematics

100 questions · 100 marks · 120 min · 1 mark each · 1/3 negative marking · (IMA/INA/AFA only — not in OTA)
Indicative distribution from a recent CDS paper — counts vary each cycle.
★ Geometry~20 Q · 20%
★ Number System~18 Q · 18%
★ Mensuration~16 Q · 16%
Trigonometry~12 Q · 12%
Algebra~9 Q · 9%
Time, Speed & Distance~5 Q · 5%
Statistics (Mean/Median/Mode)~5 Q · 5%
Interest (SI & CI)~4 Q · 4%
Time & Work~4 Q · 4%
Clock & Calendar~4 Q · 4%
Percentage, Profit & Loss, Mixtures, Sets~8 Q · 8%

How to read this: the exam structure (questions, marks, duration, marking) is verified against the official pattern. Paper structure verified against the UPSC CDS scheme. UPSC publishes no official per-topic counts; the Mathematics distribution below is indicative (from a recent CDS paper) and English/GK show official syllabus areas only. Use the topic split for prioritisation — ★ marks consistently high-weight topics — not as official quotas. Sources: upsc.gov.in (CDS notification) · collegedekho CDS paper analysis.

The SSB stage

CDS candidates are assessed on the same 15 OLQs across the 5-day SSB battery.

PrepForce simulates exactly this — a voice Personal Interview and the psychology battery, scored on the 15 OLQs.