Every CAT Quant Formula You Need for 2026: The Complete Master List Organised by Topic
A complete master list of every CAT quant formula organised by topic: number systems, algebra, geometry, arithmetic, and modern math. Includes a 4-step revision method for converting formula knowledge into exam-day recall.

Every CAT Quant Formula You Need for 2026: The Complete Master List Organised by Topic
You do not need 200 formulas to score well in CAT Quant. You need 50-60 core CAT quant formulas that cover every topic the exam tests, and you need to know when to apply each one. The problem most aspirants face is not a lack of formulas but a lack of organisation. Formulas are scattered across 15 different PDFs, 10 YouTube playlists, and a notebook with illegible handwriting from three months ago.
This is the master list of all formulas for CAT 2026 Quant, organised by topic. Bookmark it, screenshot it, or copy it into your own revision sheet. Every formula here has appeared in CAT papers within the last 5 years. If a formula is not on this list, you probably do not need it for CAT.
CAT Quant Formulas: Number Systems
Number systems carry 4-6 questions per CAT paper. The formulas below cover divisibility, remainders, HCF/LCM, and factorial properties. These are the most frequently tested CAT quant formulas in this topic area, and each one has appeared in at least 2 of the last 5 CAT papers.
| Formula | What It Does |
|---|---|
HCF(a,b) x LCM(a,b) = a x b | Relates HCF and LCM for two numbers |
n! has floor(n/p) + floor(n/p^2) + ... trailing zeros of prime p | Count trailing zeros or highest power of p in n! |
Euler's totient: phi(n) = n x (1-1/p1)(1-1/p2)... | Count of numbers less than n coprime to n |
Number of factors of n = (a1+1)(a2+1)... where n = p1^a1 x p2^a2... | Total factor count from prime factorisation |
Sum of factors = (p1^(a1+1)-1)/(p1-1) x (p2^(a2+1)-1)/(p2-1) x ... | Sum of all divisors |
Remainder of a^n / d: use cyclicity of last digit or Fermat's little theorem | Remainder problems with large exponents |
CAT Quant Formulas: Algebra
Algebra questions in CAT test equations, inequalities, functions, and logarithms. The formulas below are the ones that save time on CAT day. Quadratic equations and logarithm properties together account for about 60% of all CAT algebra questions based on analysis of recent papers.
| Formula | What It Does |
|---|---|
ax^2 + bx + c = 0: x = (-b +/- sqrt(b^2-4ac)) / 2a | Quadratic formula |
Sum of roots = -b/a, Product of roots = c/a | Vieta's formulas for quadratics |
log(ab) = log(a) + log(b), log(a/b) = log(a) - log(b) | Logarithm product and quotient rules |
log_a(b) = log(b)/log(a) = 1/log_b(a) | Change of base formula |
AM >= GM >= HM (for positive numbers) | Arithmetic mean, geometric mean, harmonic mean inequality |
|a+b| <= |a| + |b| and |a-b| >= ||a| - |b|| | Triangle inequality for absolute values |
For CAT, the AM-GM inequality solves 80% of "find maximum/minimum value" questions in under 30 seconds. If a question asks for the minimum of (x + 1/x) for positive x, AM-GM gives you the answer immediately: minimum = 2 (when x = 1/x, i.e., x = 1). Practise recognising AM-GM opportunities in your CAT practice question sets.
CAT Quant Formulas: Geometry and Mensuration
Geometry has the highest formula density in the CAT quant formulas list. Triangles, circles, and quadrilaterals each carry their own set of formulas. The ones below are tested most frequently. Memorise the triangle area formulas first; they appear in some form in every single CAT paper.
| Formula | What It Does |
|---|---|
Area of triangle = (1/2) x base x height | Basic triangle area |
Heron's: Area = sqrt(s(s-a)(s-b)(s-c)), s = (a+b+c)/2 | Triangle area from three sides |
Area of equilateral triangle = (sqrt(3)/4) x a^2 | Equilateral triangle with side a |
Circumradius R = abc / 4A, Inradius r = A/s | Circumscribed and inscribed circle radii |
Area of circle = pi x r^2, Circumference = 2 x pi x r | Circle basics |
Arc length = (theta/360) x 2pi x r, Sector area = (theta/360) x pi x r^2 | Arc and sector from central angle |
Similar triangles: sides proportional, areas in ratio of squares of sides | Similar triangle properties |
Pythagoras: a^2 + b^2 = c^2 (right triangle) | Right triangle side relationship |
- Common Pythagorean triples for CAT: (3,4,5), (5,12,13), (7,24,25), (8,15,17)
- 30-60-90 triangle sides ratio: 1 : sqrt(3) : 2
- 45-45-90 triangle sides ratio: 1 : 1 : sqrt(2)
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Practise CAT Quant Questions by TopicCAT Quant Formulas: Arithmetic
Arithmetic topics (time-speed-distance, profit/loss, percentages, averages, mixtures, time-work) together account for 8-10 questions per CAT paper. These all formulas for CAT arithmetic section are among the most frequently tested and among the easiest to apply once memorised.
| Topic | Formula |
|---|---|
| Speed-Distance-Time | Distance = Speed x Time, Average speed = 2ab/(a+b) for equal distances |
| Relative Speed | Same direction: |s1-s2|, Opposite: s1+s2 |
| Profit/Loss | Profit% = (SP-CP)/CP x 100, Loss% = (CP-SP)/CP x 100 |
| Markup | SP = MP x (1 - Discount%), MP = CP x (1 + Markup%) |
| Simple Interest | SI = P x R x T / 100 |
| Compound Interest | A = P(1 + R/100)^T |
| Percentages | %change = (New-Old)/Old x 100, Successive: a+b+ab/100 |
| Averages | Avg = Sum/Count, Weighted avg = (w1.x1 + w2.x2)/(w1+w2) |
| Mixtures | Alligation: (C2-Cavg)/(Cavg-C1) = n1/n2 |
| Time-Work | If A does in x days, B in y days, together: 1/x + 1/y = 1/T |
When two successive percentage changes of a% and b% are applied, the net effect is (a + b + ab/100)%. This single formula eliminates 2-3 calculation steps in profit/loss and percentage change questions. If a shopkeeper marks up by 40% and gives a 20% discount, net profit = 40 + (-20) + (40 x -20)/100 = 40 - 20 - 8 = 12%. This is one of the most time-saving CAT quant formulas in the arithmetic section.
CAT Quant Formulas: Modern Math
Modern math covers permutations, combinations, probability, and arithmetic/geometric progressions. These topics carry 3-5 questions per CAT paper. The formulas below are the core set you need for all formulas for CAT modern math questions. Progressions formulas are particularly useful because they appear in both direct and disguised forms across multiple question types.
| Topic | Formula |
|---|---|
| Permutations | nPr = n! / (n-r)! |
| Combinations | nCr = n! / (r! x (n-r)!) |
| Probability | P(A) = Favourable / Total, P(A or B) = P(A) + P(B) - P(A and B) |
| Conditional | P(A|B) = P(A and B) / P(B) |
| AP: nth term | a_n = a + (n-1)d |
| AP: Sum | S_n = n/2 x (2a + (n-1)d) = n/2 x (first + last) |
| GP: nth term | a_n = a x r^(n-1) |
| GP: Sum (finite) | S_n = a(r^n - 1)/(r - 1) when r != 1 |
| GP: Sum (infinite) | S = a/(1-r) when |r| < 1 |
How to Use This CAT Quant Formulas List
A master list is useful only if you convert it into active knowledge. Reading this page once does not make these formulas available during the exam. Here is a revision method that works, based on how top CAT scorers prepare their formula sheets for the CAT 2026 exam.
- Copy the formulas by hand into your own notebook. The physical act of writing reinforces memory. Do not print this page and assume you will remember it.
- Solve 5 problems per formula using the CAT practice question bank. A formula you have never applied in a problem is a formula you do not actually know.
- Revise the full list every Sunday during your CAT preparation. Write each formula from memory, then check against this master list. Mark the ones you forgot. Those marked formulas get extra revision the following week.
- Create a "last mile" sheet of the 20 formulas you forget most often. Review this sheet in the 48 hours before CAT. Your CAT 2026 preparation plan should include these revision slots explicitly.
This CAT 2026 formula sheet approach turns passive reading into active recall, which is the only form of memory that works under exam pressure. If you are preparing with Optima Learn's personalised study plan, the topic sequencing already accounts for formula revision cadence alongside problem solving. Use your CAT score prediction to track how your Quant accuracy improves as you internalise more formulas.
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