You can use a calculator to solve problems and avoid writing out extensive calculations on the ACT Mathematics Test. However, according to the ACT website, the ACT prohibits some types of calculators, such as "calculators with built-in computer algebra systems." If you bring a calculator with prohibited features into the test, you will be dismissed and your test will not be scored.

Four-Function Calculator

You may use any basic four-function calculator on the ACT. Four-function calculators perform the basic arithmetic operations of addition, subtraction, multiplication and division. They may also be able to perform other basic tasks such as square roots and percentage conversations. The low cost and easy functionality of a four-function calculator may make it appealing for ACT math.

Scientific or Graphing Calculator

The ACT permits scientific or graphing calculators that do not include prohibited features such as built-in algebra systems. Scientific and graphing calculators allow you to perform more complex tasks, such as graphing linear or nonlinear equations, performing trigonometry expressions and basic statistical procedures. Though these features can be advantageous, you should not use a calculator on the ACT that is more complicated than you understand. All of the questions on the test can be solved by hand -- the calculator is just intended to speed up the process. You will solve math problems more efficiently on a familiar calculator than on a more advanced calculator on which you do not know how to use the same functions.

Prohibited Calculators

The ACT prohibits calculators with built-in algebra systems, handheld or laptop computers, writing pads, cell phone calculators or calculators with a typewriter keypad. Other calculators may only be admitted with modification; for example, calculators that make noise must be muted and calculators with power cords must have those cords removed.

Using Your Calculator Effectively

Before using your calculator, you should first understand what the question is asking and decide the best method for solving the problem. Most ACT math will not be overly complex or require extensive use of the calculator to solve the problems. Use your calculator only as a shortcut for math steps that would take too long to write out in your notes. You may bring a spare calculator in case your main calculator breaks or loses battery power, but you may not share with others and the testing staff will not have backup calculators available.