Digital SAT Formula Sheet: Every Formula You Need

Digital SAT Formula Sheet: What You Get on Test Day

The digital SAT provides a formula reference sheet at the start of the Math section. It's accessible through the testing interface throughout both Math modules. Knowing exactly what's on it — and what isn't — is one of the most practical things you can do before your test date.

Here's the thing: most students don't use the formula sheet efficiently. They either forget it exists or they spend time scrolling through it during the test when they could have memorized those formulas in advance. The formula sheet is a backup, not a crutch. The students who score highest are the ones who know the formulas cold and use the sheet only to double-check.

Every Formula on the Digital SAT Reference Sheet

The SAT math reference sheet includes the following:

Area formulas:

• Rectangle: A = lw
• Triangle: A = ½bh
• Circle: A = πr²
• Circle circumference: C = 2πr

Volume formulas:

• Rectangular solid (box): V = lwh
• Cylinder: V = πr²h
• Sphere: V = (4/3)πr³
• Cone: V = (1/3)πr²h
• Pyramid: V = (1/3)lwh

Pythagorean theorem and special right triangles:

• Pythagorean theorem: a² + b² = c²
• 30-60-90 triangle: sides in ratio 1 : √3 : 2
• 45-45-90 triangle: sides in ratio 1 : 1 : √2

Additional facts provided:

• The number of degrees in a circle: 360
• The number of degrees in a triangle: 180
• The number of radians in a circle: 2π

That's the complete list. Twelve formulas/facts. Print them out and look at them — it's a short list, and many test-takers are surprised by how basic some of it is.

What's NOT on the SAT Formula Sheet (Memorize These)

Here's where most students make a costly mistake: they assume that if a formula isn't on the sheet, it won't be tested. That's wrong. The SAT tests plenty of concepts and formulas that aren't provided. You're expected to know these from your math education.

Algebra formulas you must know:

• Slope formula: m = (y₂ - y₁) / (x₂ - x₁)
• Slope-intercept form: y = mx + b
• Point-slope form: y - y₁ = m(x - x₁)
• Standard form of a linear equation: Ax + By = C
• Quadratic formula: x = (-b ± √(b² - 4ac)) / 2a
• Standard form of a quadratic: y = ax² + bx + c
• Vertex form of a quadratic: y = a(x - h)² + k
• Difference of squares: a² - b² = (a + b)(a - b)
• Perfect square trinomial: (a + b)² = a² + 2ab + b²

Geometry concepts not on the sheet:

• Midpoint formula: ((x₁ + x₂)/2, (y₁ + y₂)/2)
• Distance formula: d = √((x₂ - x₁)² + (y₂ - y₁)²)
• Area of a trapezoid: A = ½(b₁ + b₂)h
• Arc length and sector area: you need to understand the proportion approach

Statistics and data analysis:

• Mean, median, mode definitions and how to calculate them
• Percent change formula: (new - old) / old × 100
• Probability: favorable outcomes / total outcomes
• Linear regression line interpretation (y-intercept meaning, slope meaning)

Trigonometry basics:

• SOH-CAH-TOA (sin = opposite/hypotenuse, cos = adjacent/hypotenuse, tan = opposite/adjacent)
• Complementary angle relationships: sin(x) = cos(90° - x)

None of these are on the formula sheet. All of them appear in the actual SAT Math section regularly.

How to Use the Formula Sheet Strategically

On test day, the formula sheet is available from the start of the Math section — you don't have to do anything special to access it. In the Bluebook testing interface, there's a reference button that pulls it up in a sidebar without leaving the question.

Here's the strategic approach: don't rely on it during timed practice. When you practice, work through geometry and formula-based problems without looking at the sheet. If you get a problem wrong because you couldn't remember a volume formula, that's actually valuable — you identified a gap. Then review the formula and practice that problem type again. By test day, the formulas on the sheet should feel redundant — things you already know.

If you hit a problem on the real test where you genuinely can't remember a formula that is on the sheet, take two seconds to pull it up. It's better to use it than to guess at a formula you're uncertain about. But those situations should be rare if you've prepared properly.

Geometry and Volume: The Most Commonly Referenced Formulas

Statistically, the volume formulas — especially cylinder and sphere — show up in Digital SAT problems more than the rectangle area or basic triangle formulas (which most students know automatically). If you're going to get extra reps on any part of the sheet, make it the 3D shapes.

Typical SAT geometry problems involving these formulas don't just ask you to plug in numbers. They ask compound questions: "A cylinder is melted down and reformed into a sphere of the same volume — what's the radius of the sphere?" You need to set the cylinder volume formula equal to the sphere volume formula and solve for the unknown. Just knowing the formula isn't enough; you need to know how to use it in multi-step problems.

The khan academy dsat practice sections include geometry problems that require multi-step formula application. Work through those problem sets specifically to build fluency with the provided formulas in realistic contexts.

The 30-60-90 and 45-45-90 Triangles

These special right triangles appear in the reference sheet and show up regularly on the SAT. Know them cold — including when to apply each one and how to derive missing side lengths from the ratios.

For the 30-60-90 triangle with hypotenuse 2x: the short leg is x and the long leg is x√3. For the 45-45-90 triangle with legs of length x: the hypotenuse is x√2.

SAT problems involving these triangles often embed them inside larger figures — an equilateral triangle divided into two 30-60-90 triangles, or a square divided diagonally into two 45-45-90 triangles. Recognizing when you're looking at one of these special triangles, even when it's not obvious, is the actual skill being tested.

Formula Sheet Mastery: The Last-Mile Preparation

If you're two or three weeks out from your test date, formula review should be a small but consistent part of your daily routine. Five minutes in the morning — write out the formula sheet from memory, check it, identify any gaps. Do that for two weeks and you'll have the sheet memorized completely without it feeling like a grind.

Spend more time on the formulas that aren't provided — the quadratic formula especially, since it's testable and not intuitive to derive under pressure. Know when to factor versus when to use the quadratic formula (factoring is faster when it works; the formula is the backup). Know the vertex formula h = -b/(2a) for finding the vertex of a parabola without completing the square.

The Digital SAT Math section is 44 questions across two adaptive modules. Formula fluency — both the provided formulas and the ones you've memorized — removes a category of potential errors from your exam. That's points you're not leaving on the table because you couldn't remember a volume formula or blanked on the distance formula.

For more practice on the types of math problems where these formulas are applied, work through the dsat practice test questions in the geometry and advanced math categories. You want to see these formulas in context — embedded in multi-step problems — not just isolated in a list.