SAT Math formulas: what's on the reference sheet and what to memorise

TutorAura guide · Updated 22 October 2026

The Digital SAT gives you a reference sheet with common geometry formulas for every Math question (College Board). It does not give you the algebra, data and trigonometry facts that most questions need. Here is everything on the sheet, followed by the formulas worth memorising, with a quick example of each.

Key takeaways

The reference sheet covers area, volume, the Pythagorean theorem and special right triangles.
Algebra formulas (slope, quadratics, exponents) are not provided: learn them.
Know percentage change, averages and the circle equation by heart.
The built-in calculator can check work, but you still need to know which formula to use.

On the reference sheet (provided)

Shape or fact	Formula
Circle	$A = \pi r^2$ , $C = 2\pi r$
Rectangle	$A = \ell w$
Triangle	$A = \tfrac{1}{2}bh$
Pythagorean theorem	$c^2 = a^2 + b^2$
Special right triangles	$30^\circ$ - $60^\circ$ - $90^\circ$ : $x,\ x\sqrt{3},\ 2x$ ; $45^\circ$ - $45^\circ$ - $90^\circ$ : $s,\ s,\ s\sqrt{2}$
Rectangular prism	$V = \ell wh$
Cylinder	$V = \pi r^2 h$
Sphere	$V = \tfrac{4}{3}\pi r^3$
Cone	$V = \tfrac{1}{3}\pi r^2 h$
Pyramid	$V = \tfrac{1}{3}\ell wh$

It also states that a circle has 360 degrees (or $2\pi$ radians) of arc and that a triangle's angles add up to 180 degrees.

Lines and linear functions (memorise)

Slope: $m = \dfrac{y_2 - y_1}{x_2 - x_1}$
Slope-intercept form: $y = mx + b$ ( $b$ is the $y$ -intercept)
Parallel lines have equal slopes; perpendicular slopes multiply to $-1$ .

Example: the line through $(1, 3)$ and $(4, 9)$ has slope $\dfrac{9-3}{4-1} = 2$ , so $y = 2x + 1$ .

Quadratics and exponents (memorise)

Quadratic formula: $x = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a}$
Discriminant $b^2 - 4ac$ : positive → two real solutions, zero → one, negative → none.
Vertex form: $y = a(x - h)^2 + k$ has vertex $(h, k)$ .
Exponent rules: $a^m \cdot a^n = a^{m+n}$ , $\dfrac{a^m}{a^n} = a^{m-n}$ , $(a^m)^n = a^{mn}$ , $a^0 = 1$ , $a^{-n} = \dfrac{1}{a^n}$ .
Exponential growth: $y = a(1 + r)^t$ ; decay: $y = a(1 - r)^t$ .

Example: $x^2 - 5x + 6 = 0$ has discriminant $25 - 24 = 1 > 0$ , so two solutions: $x = 2$ and $x = 3$ .

Percentages, ratios and data (memorise)

Percentage change: $\dfrac{\text{new} - \text{old}}{\text{old}} \times 100\%$
Increase by $p\%$ : multiply by $1 + \tfrac{p}{100}$ ; decrease: multiply by $1 - \tfrac{p}{100}$ .
Mean: sum of values ÷ number of values. Median: the middle value when ordered.
Probability: favourable outcomes ÷ total outcomes.

Example: a price rises from 40 to 50: $\dfrac{50 - 40}{40} \times 100\% = 25\%$ . A 20% rise followed by a 20% fall isn't back to the start: $1.2 \times 0.8 = 0.96$ , a 4% fall overall.

Circles and trigonometry (memorise)

Circle equation: $(x - h)^2 + (y - k)^2 = r^2$ , centre $(h, k)$ , radius $r$ .
Arc length: $\dfrac{\theta}{360} \times 2\pi r$ ; sector area: $\dfrac{\theta}{360} \times \pi r^2$ .
SOH CAH TOA: $\sin\theta = \dfrac{\text{opp}}{\text{hyp}}$ , $\cos\theta = \dfrac{\text{adj}}{\text{hyp}}$ , $\tan\theta = \dfrac{\text{opp}}{\text{adj}}$ .
$\sin x^\circ = \cos(90 - x)^\circ$ .
Radians: $180^\circ = \pi$ radians.

Example: $(x - 2)^2 + (y + 1)^2 = 9$ is a circle centred at $(2, -1)$ with radius $3$ . Our right-triangle trigonometry guide has practice questions.

Knowing formulas isn't enough

Most missed SAT Math questions aren't about forgetting a formula: they're about choosing the right one, setting it up from words, or answering a different question than the one asked. Practise mixed questions under time, and use the calculator to check. See our SAT Math tips, then try the free Digital SAT Math practice test with the reference sheet and calculator built in.

Frequently asked questions

Does the SAT give you a formula sheet?

Yes. The Digital SAT has a reference sheet with area and volume formulas, the Pythagorean theorem, special right triangles and a few angle facts. It doesn't include algebra formulas such as the quadratic formula.

Is the quadratic formula on the SAT reference sheet?

No. You need to know it, along with the discriminant, slope and exponent rules.

What formulas should I memorise for the SAT?

Slope and line forms, the quadratic formula and discriminant, exponent rules, percentage change, exponential growth and decay, the circle equation, arc length and sector area, and SOH CAH TOA.

Can I use a calculator for every SAT Math question?

Yes. The built-in Desmos calculator (or your own approved calculator) is allowed throughout the Math section.

Sources

Testing Tools (Bluebook). College Board.
Assessment Framework for the Digital SAT Suite. College Board.
SAT Practice Test #9 (Digital). College Board.

SAT Math tips: pacing, the calculator, grid-ins and common traps

Pace at about 95 seconds a question, use the calculator and reference sheet well, enter grid-ins correctly and avoid common traps.

Digital SAT Math

Topic guides and practice for every Digital SAT Math domain.

Free Digital SAT practice tests

A full-length, timed, adaptive practice test and section tests, free with no sign-up.

Quadratic equations

Solve quadratics by factorising, the quadratic formula and completing the square; use the discriminant and vertex form.