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CDS preparation with Prepology
Prepology is an adaptive exam-preparation app for CDS (Combined Defence Services Examination). For CDS it has 1,500+ original practice questions across English, Elementary Mathematics and General Knowledge (79 topics), timed mock tests on the exam pattern (three papers of 2 hours and 100 marks each), a personalised daily study plan, spaced revision and an AI mentor that explains questions. It runs in the browser and on Android, is free to start, and Plus costs ₹49 a month or ₹499 a year. It is for learners aged 18 and over.
CDS is the Union Public Service Commission’s exam for the Indian Military Academy, Indian Naval Academy, Air Force Academy and Officers’ Training Academy.
- 1,500+original practice questions
- 3subjects
- 79topics covered
- ₹0to start · Plus ₹49/month
What Prepology offers for CDS
- Chapter-wise practice: 1,500+ original CDS-style questions across 79 topics, pitched at your level, with an explanation after every answer.
- Timed mock tests (Plus): full papers on the CDS pattern below, with the exam’s marking and negative marking.
- A personalised daily study plan: built around your classes and study hours, weighted by how much each topic counts in the exam, and rebuilt when you fall behind.
- Spaced revision: topics and missed questions come back for review before you forget them.
- AI Mentor: explains questions and answers doubts about your plan and topics.
- Test history and retakes: review every mock test you have taken and retake it.
- Syllabus coverage: see which CDS topics you have practised and which are not assessed yet.
CDS exam pattern
Each CDS paper is 2 hours and 100 marks: English (120 questions), General Knowledge (120 questions) and Elementary Mathematics (100 questions). Officers’ Training Academy candidates take only English and General Knowledge. A wrong answer loses one third of that question’s marks.
| Section | Questions | Marks if right | Marks if wrong |
|---|---|---|---|
| English | 120 | +0.83 | −⅓ of marks |
| General Knowledge | 120 | +0.83 | −⅓ of marks |
| Elementary Mathematics | 100 | +1 | −⅓ of marks |
Question counts follow recent papers. Prepology’s General Knowledge questions cover the static syllabus, not current events. Source: UPSC CDS notification (upsc.gov.in). Exam patterns can change; always check the official notification.
CDS subjects and topics covered
Topics follow the official CDS syllabus. Each topic has its own practice questions, revision and progress.
English 14 topics · 250+ questions
- Spotting Errors
- Sentence Improvement
- Fill in the Blanks (Sentence Completion)
- Sentence Transformation (Voice, Narration, Simple-Complex-Compound)
- Ordering of Words in a Sentence
- Ordering of Sentences (Para Jumbles)
- Synonyms
- Antonyms
- Idioms and Phrases
- One-Word Substitution
- Homonyms, Confusable Words and Spellings
- Verbal Analogy
- Reading Comprehension
- Cloze Test
Elementary Mathematics 25 topics · 500+ questions
- Polynomials, Factorisation and Remainder Theorem
- Laws of Indices and Surds
- Rational Expressions and Conditional Identities
- Linear Equations and Inequations in Two Variables
- Quadratic Equations
- Set Language and Notation
- Trigonometric Ratios and Identities
- Heights and Distances
- Number System and Simplification
- Divisibility, Primes and Factors
- HCF and LCM
- Percentage
- Profit and Loss
- Simple and Compound Interest
- Ratio, Proportion and Variation
- Time and Work
- Time and Distance
- Logarithms
- Lines, Angles and Triangles
- Similar Triangles, Centres of a Triangle and Loci
- Parallelograms, Rectangles and Squares
- Circles, Tangents and Normals
- Area and Perimeter of Plane Figures
- Surface Area and Volume of Solids
- Statistics
General Knowledge 40 topics · 800+ questions
- Matter, Elements, Mixtures and Compounds
- Atomic Structure and Valency
- Air, Water and Common Gases
- Acids, Bases, Salts; Oxidation and Reduction
- Carbon and its Forms
- Chemistry in Everyday Life
- Living Things, Cells and Tissues
- Growth and Reproduction in Plants and Animals
- Human Body and its Organs
- Food, Nutrition, Health and Diseases
- The Solar System and Space
- Eminent Scientists and Discoveries
- The Earth: Shape, Latitudes, Longitudes and Time
- Rocks, Landforms, Earthquakes and Volcanoes
- Oceans: Currents and Tides
- Atmosphere, Weather and Climate
- World Physical Geography
- Physical Geography of India
- Economic Geography of India
- Ancient India
- Medieval India
- Indian Art and Culture
- Advent of Europeans, British Expansion and 1857
- Indian Freedom Movement
- Forces Shaping the Modern World
- Properties of Matter, Density and Pressure
- Motion, Force, Gravitation, Work and Energy
- Heat and Temperature
- Sound
- Light and Optical Instruments
- Magnetism and Electricity
- Working Principles of Everyday Devices
- Indian Constitution
- Union and State Government
- Panchayati Raj, Co-operatives and Community Development
- Indian Economy Basics and Planning
- National and International Organisations
- Environment and Ecology
- Sports (Static)
- Defence Technology and Security Forces
CDS preparation: questions and answers
Is Prepology free for CDS preparation?
Yes, you can start free. The Free plan includes 20 practice questions a day, the daily study plan, revision, notes, flashcards and 20 AI Mentor messages a day. Plus (₹49 a month or ₹499 a year) raises practice to 200 questions a day, adds timed CDS mock tests and allows 150 Mentor messages a day.
Are the questions taken from past CDS papers?
No. They are original questions written for Prepology to the CDS syllabus and pattern, each with a worked explanation. Questions are checked by a reviewer, and you can report a mistake from the app.
Do the mock tests follow the real CDS pattern?
They follow the pattern on this page (three papers of 2 hours and 100 marks each). Exam bodies can change the pattern, so check the official notification before your exam.
Is Prepology affiliated with the UPSC or the armed forces?
No. Prepology is an independent study aid. It is not affiliated with or endorsed by the UPSC or the armed forces or any other exam-conducting body.
Who can use Prepology?
Anyone aged 18 or over. Use it in a browser or install the Android app; both sync to the same account.
Start preparing for CDS
Set up in about three minutes: pick CDS, add your study hours, and get your first study plan. No payment needed to start.
Related: NDA, AFCAT, SSB OIR. All exams on Prepology.