CDS Exam Important Topics 2026: Subject-Wise Guide

UPSC Combined Defence Services (CDS) exam is a national-level defence services exam with a pass rate of 0.1% to 0.33%. Due to the great difficulty level of this examination, students get many pieces of advice from their teachers to complete the CDS exam syllabus easily and be appropriately prepared for the exam. One of these pieces of advice includes focusing more on the important CDS topics of the three subjects - English, General Knowledge, and Elementary Mathematics - during your preparation. Such topics include those that carry the maximum relevance and frequency of appearing in the written exam’s question paper.

What is the CDS Written Exam Pattern?

The CDS written examination is conducted for candidates all across India to apply to IMA, INA, AFA, and OTA. For IMA, INA, and AFA, one has to appear for English, General Knowledge, and Elementary Mathematics exams, while OTA candidates appear only for English and General Knowledge papers in the CDS exam pattern. Each of these papers is objective in nature and is two hours long, leading to a total CDS exam duration of 6 hours and a total of 300 marks.

What Are the CDS Elementary Mathematics Important Topics?

Elementary Mathematics is considered tough to clear by the majority of students who appear for CDS. The CDS Maths syllabus covers important chapters such as arithmetic, algebra, trigonometry, geometry, mensuration, and statistics, which mainly carry the CDS Maths important topics, among many other chapters.

Arithmetics

• Number System

• Natural numbers, integers, rational and real numbers

• Decimals and fundamental operations

• HCF and LCM

• Percentage

• Ratio and proportion

• Unitary method

• Profit and loss

• Simple and compound interest

• Time and work

• Time, speed and distance

• Variation

• Elementary number theory and divisibility

Algebra

• Basic algebraic operations

• Factorisation

• Remainder theorem

• HCF and LCM of algebraic expressions

• Polynomials

• Quadratic equations

• Relation between roots and coefficients

• Linear inequations

• Sets

• Rational expressions

• Laws of indices

Geometry, Trigonometry, and Mensuration

• Geometry: Lines and angles along with shapes like triangles, parallelograms, rectangles, squares, circles, congruency, similarity, tangents, and loci.

• Trigonometry: Sine, cosine, standard-angle values, identities, heights, along with distances.

• Mensuration: Areas of squares, rectangles, triangles, parallelograms and circles, surface area and volume of cuboids, cylinders, cones and spheres, and composite figures

Statistics

• Collection and tabulation of data

• Frequency distributions

• Mean

• Median

• Mode

• Basic interpretation of data

• Elementary graphical representation

What Are the CDS General Knowledge Important Topics?

The CDS General Knowledge (GK) syllabus consists of a wide range of subjects that include History, Geography, General Science, and Economics along with CDS current affairs. For all the subjects that are a part of this 100-mark paper, the following are the CDS exam important topics that you study at the best CDS coaching:

History

• Ancient Indian history: Major civilizations, religions, kingdoms and cultural developments

• Medieval India: Important dynasties, administration and cultural developments

• Modern Indian history

• British expansion in India

• Social and religious reform movements

• Revolt of 1857

• Indian National Congress and major developments

• Gandhian movements

• Important constitutional developments

• Indian freedom struggle and independence

Geography

• Mountains, plateaus, plains, and rivers

• Indian rivers

• Climate

• Soils and agriculture

• Natural resources

• Minerals

• Population & settlements

Indian Polity

• The Constitution of India

• The preamble

• The fundamental rights and duties

• President and Vice President

• Prime Minister and the council of ministers

• Parliament

• Supreme Court and High Courts

• Constitutional and statutory bodies

• Elections

• Centre-state relations

General Science

• Physics: Motion, force, work, energy, heat, light, sound, and electricity.

• Chemistry: Elements, compounds, acids, bases, salts, metals, and non-metals.

• Biology: Human body system, nutrition, diseases, cells, plants, reproduction, and ecology.

Current Affairs

• National and international events

• Government policies and initiatives

• Developments in the defence sector

• Military exercises

• Awards and honours

• Sports

• Science and technological developments

• Space missions

• International organisations and summits

• Major economic and environmental developments

What Are the CDS English Important Topics?

The CDS English syllabus tests a candidate's understanding of English grammar, vocabulary, sentence construction, and comprehension. Studying its important topics for CDS exam is another crucial part of how to crack CDS exam.

English Grammar

• Speech

• Subject-verb agreement

• Conjunctions

• Pronouns

• Adjectives

• Adverbs

• Active voice

• Passive voice

• Tenses

• Articles

• Prepositions

Comprehension & Sentence Arrangement

• Passages

• Sentence ordering

• Para jumbles

• Sentence completion

• Flow and cohesion

Vocabulary

• Synonyms

• Antonyms

• Substitutions

• Idioms and phrases

• Word meanings

• Commonly confused words

• Contextual vocabulary

• Usage of words in sentences

How Should CDS Important Topics 2026?

A good CDS exam preparation strategy should balance proper understanding of all topics, revisions, mock tests, and tips from your teachers. As for the understanding part, you should focus on the important topics and set a topic-wise priority for all subjects. Below are the prioritizable topics of all subjects:

• Mathematics: Set your priority on arithmetic and algebra, followed by geometry, trigonometry, and mensuration before moving to further topics.

• GK: Focus on History followed by Geography, Polity, and Science with regular revision of Current Affairs.

• English: Strengthen grammar and vocabulary while practising comprehension and sentence-based questions.

Conclusion

CDS is an exam in which more than 99% of candidates fail. For an exam with such a difficulty level, you should make sure that your preparation is perfect. Two parts of achieving this perfection in your studies for the CDS written exam include focusing on the important topics of all subjects and choosing the right coaching academy for guidance in preparation.

Enroll in Prahar Defence Academy, Nagpur, and achieve perfection in your CDS preparation with experienced teachers.

Frequently Asked Questions (FAQs)

Q. Can I apply for CDS without Maths?

Yes, you can apply for CDS without Maths to join the Officers Training Academy (OTA), in which you only need to take the English and General Knowledge papers.

Q. How many months of current affairs are required for CDS?

You need to study the current affairs of the last 6 to 8 months for your CDS exam.

Q. Which Maths is required for CDS?

The CDS exam requires Elementary Mathematics at the Class 10 level.

Q. What is the syllabus for CDS Mathematics?

The CDS Mathematics syllabus consists of arithmetic, number theory, algebra, trigonometry, geometry, mensuration, and statistics at the Class 10 level.

Q. Is 150 a good score in CDS?

Yes, 150 is a good score in CDS to meet the cutoff and crack the written exam, no matter whether you are applying for IMA, INA, AFA, or OTA.