SAT Math Formulas
SAT Math Formulas are easiest to remember when you see them used. This page lists the key Digital SAT math formulas for the Digital SAT with worked examples and shows which ones the in-test reference sheet gives you.
On the Digital SAT you can open a reference sheet during the Math section. It gives area and circumference of a circle, area of a rectangle and triangle, the Pythagorean theorem, special right triangles, and volumes of a rectangular prism, cylinder, sphere, cone and pyramid, plus three facts: a circle has 360 degrees (2π radians) and the angles in a triangle add up to 180 degrees. Everything else, such as slope, the quadratic formula and percent change, you need to know.
Given to you in the test
You do not need to memorise these, but knowing them saves time.
A = πr² · C = 2πrA = ℓwA = ½bhc² = a² + b²30°-60°-90°: x, x√3, 2x
45°-45°-90°: s, s, s√2V = ℓwhV = πr²hV = (4/3)πr³V = (1/3)πr²hV = (1/3)ℓwhCircle: 360° = 2π rad
Triangle: angles sum to 180°Algebra formulas to know
m = (y₂ − y₁) / (x₂ − x₁)Quick check: Line through (1, 3) and (4, 12): slope?
(12 − 3)/(4 − 1) = 3
y = mx + bQuick check: Slope 2, y-intercept −5: equation?
y = 2x − 5
Parallel: equal slopes · Perpendicular: m₁m₂ = −1Quick check: Slope perpendicular to y = 4x + 1?
−1/4
Same slope, different interceptsQuick check: For which k does 2x + ky = 7 have no solution with 4x + 6y = 1?
k = 3 (lines parallel, intercepts differ)
Advanced Math formulas to know
x = (−b ± √(b² − 4ac)) / (2a)Quick check: Solve x² − 6x + 5 = 0.
x = 1 or x = 5
b² − 4ac > 0: 2 real roots · = 0: 1 · < 0: noneQuick check: How many real solutions does x² + 4x + 7 = 0 have?
16 − 28 < 0, so none
y = a(x − h)² + k, vertex (h, k)Quick check: Vertex of y = 2(x − 3)² + 1?
(3, 1)
For ax² + bx + c: sum = −b/a, product = c/aQuick check: Sum of the roots of 2x² − 10x + 3 = 0?
5
aᵐ·aⁿ = aᵐ⁺ⁿ · (aᵐ)ⁿ = aᵐⁿ · a^(1/n) = ⁿ√aQuick check: Write 8^(2/3) as an integer.
4
y = a(1 ± r)ᵗQuick check: A $500 balance grows 4% a year. Value after t years?
500(1.04)ᵗ
Problem-Solving and Data Analysis formulas to know
(new − old) / old × 100%Quick check: Price rises from $40 to $50. Percent increase?
25%
sum of values ÷ number of valuesQuick check: Mean of 4, 7, 10, 15?
9
favourable outcomes ÷ total outcomesQuick check: 3 red and 5 blue counters: P(red)?
3/8
multiply by conversion factors so units cancelQuick check: 72 km/h in m/s?
20 m/s
Geometry and Trigonometry formulas to know
sin = opp/hyp · cos = adj/hyp · tan = opp/adjQuick check: Right triangle, opposite 3, hypotenuse 5: sin θ?
3/5
sin x° = cos(90° − x°)Quick check: If sin 25° = k, what is cos 65°?
k
(x − h)² + (y − k)² = r²Quick check: Centre and radius of (x − 2)² + (y + 1)² = 9?
Centre (2, −1), radius 3
arc = (θ/360)·2πr · sector = (θ/360)·πr²Quick check: Sector area for θ = 90°, r = 4?
4π
180° = π radiansQuick check: 60° in radians?
π/3
Practise the formulas
SAT math formulas FAQ
Do you get a formula sheet on the SAT?
Yes. The Digital SAT Math section includes a reference sheet with common geometry formulas and angle facts. It does not include algebra formulas such as slope or the quadratic formula.
Which SAT math formulas should I memorise?
Slope, slope-intercept and point-slope forms, the quadratic formula and discriminant, vertex form, exponent rules, exponential growth and decay, percent change, mean and median, basic probability, SOH CAH TOA and the equation of a circle.
Can I use a calculator on the Digital SAT?
Yes. A built-in Desmos graphing calculator is available for the entire Math section, and you can bring an approved calculator.
SAT Math Formulas FAQs
What is SAT Math Formulas?
SAT Math Formulas on Quiz Portal are a free reference of the formulas you need for the Digital SAT Math section, with worked examples.
Is SAT Math Formulas free on Quiz Portal?
Yes. Every practice question, quiz and mock on Quiz Portal is free, and you can start without creating an account. A free student account is optional and only saves your progress.
How do I practise SAT Math Formulas?
Read the formulas by topic, try the worked examples, then practise with the SAT Math domain drills.
Where can I find Digital SAT Math Formulas?
Open SAT Math Formulas above to start practising Digital SAT Math Formulas. Read the formulas by topic, try the worked examples, then practise with the SAT Math domain drills.