Free One-Page ACT Math Formula Sheet | Printable PDF

ACT Math Formula Sheet — Free One-Page PDF for Test Day

Unlike the SAT, the ACT doesn’t give you a formula sheet on test day — which means you need to memorize key formulas if you want to work faster and avoid mistakes.

We’ve created a free one-page ACT Math Formula Sheet (PDF) that includes every essential formula you’ll need for the test — from algebra and geometry to trigonometry and sequences. This way, you can study smarter and feel confident when it counts.

TLDR: ACT Math Formula Sheet

• ACT provides no formula sheet on test day — all must be memorized

• Covers algebra, geometry, trigonometry, sequences, and interest formulas

• Free one-page PDF includes every must-know rule

• Designed by Ivy-League tutors and top ACT scorers

• Helps you save time, reduce errors, and boost confidence

Why Use an ACT Math Formula Sheet?

The ACT Math section covers a wide range of topics, and while many formulas may feel familiar, it’s easy to forget one in the middle of the test. Having them memorized will help you:

• Save time on straightforward problems

• Reduce careless errors

• Focus on solving rather than recalling formulas

• Feel more confident under time pressure

💡 Tip: Since the ACT gives you no formulas, knowing these in advance is one of the easiest score-boosting strategies you can use.

ACT Math Formula Sheet

Here’s everything included in the one-page PDF:

Algebra & Coordinate Geometry

Slope Formula: m = (y2 − y1) ÷ (x2 − x1)
Slope-Intercept Form: y = mx + b
Point-Slope Form: y − y1 = m(x − x1)
Quadratic Formula: x = [−b ± √(b² − 4ac)] ÷ (2a)
Distance Formula: d = √[(x2 − x1)² + (y2 − y1)²]
Midpoint Formula: M = ((x1 + x2) ÷ 2 , (y1 + y2) ÷ 2)

Geometry – Triangles

• Pythagorean Theorem: a² + b² = c²

  
  Special Right Triangles:

• 45°–45°–90°: sides x, x, x√2

• 30°–60°–90°: sides x, x√3, 2x
  
  Trigonometric Ratios:

• sin A = opposite ÷ hypotenuse

• cos A = adjacent ÷ hypotenuse

• tan A = opposite ÷ adjacent

Tutor Tip💡: Our Harvard tutor points out that memorizing the special right triangles (30°–60°–90° and 45°–45°–90°) can save you up to two minutes per test, they appear constantly on the ACT.

Geometry – Polygons

Degree Measure in a Regular Polygon: (180 × (n − 2)) ÷ n
Sum of Interior Angles in a Polygon: 180 × (n − 2)

Geometry – Circles

Center-Radius Form of a Circle: (x − h)² + (y − k)² = r²
Area: A = π × r²
Circumference: C = 2 × π × r
Area of a Sector: A = (θ ÷ 360) × π × r²

Sequences and Series

Arithmetic Sequence: aₙ = a₁ + (n − 1)d
Arithmetic Series: Sₙ = (n ÷ 2) × (a₁ + aₙ)

Interest

Simple Interest: I = P × r × t
Compound Interest: A = P × (1 + r ÷ n)^(n × t)

Measurement & Variation

Distance, Rate, Time: D = r × t
Direct Variation: y = k × x
Inverse Variation: y = k ÷ x

How to Use This Formula Sheet

1. Download and print the one-page PDF.

2. Memorize in small chunks — don’t try to learn all at once.

3. Practice using them in real ACT questions.

4. Test yourself without looking until you can recall all of them instantly.

Final Thoughts

The ACT is as much about strategy as it is about math skills. By having every essential formula in your head, you’ll work faster, make fewer mistakes, and feel more confident.