ACT Approved Calculators (2026): Rules, Allowed Models & Tips

Calculators can be a huge help on the ACT Math section, but only if you bring the right one. The ACT has strict calculator rules, and breaking them could mean disqualification on test day.

For students, this means you need to know exactly which calculators are allowed, which models are banned, and how to use your calculator effectively during the test. For tutors, it is about giving clear guidance so students don’t make last-minute mistakes that cost them points or peace of mind.

This guide covers everything you need to know: the approved calculator list, prohibited models, usage tips, common myths, and how EdisonOS can help tutors prepare students for the ACT with confidence.
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Types of calculators allowed on the ACT

Knowing which one to bring can make a big difference. Each category has its strengths, and the right choice depends on your comfort level and math needs. If you are taking the Digital ACT, there is also a fourth option: the built-in Desmos graphing calculator available during the Math section. 

1. Graphing calculators

These are the most powerful devices you can bring. They can plot graphs, solve trigonometric functions, and handle complex equations. Models like the TI-84 Plus or Casio fx-9750GII are popular. Graphing calculators are great if you already know how to use them, but they are not required—every ACT math problem can be solved without one.

2. Scientific calculators

Scientific calculators are the “middle ground.” They handle functions like roots, trigonometry, logarithms, and statistics. They are less bulky than graphing calculators and usually faster for straightforward calculations. Many students find scientific calculators like the TI-30XS MultiView or Casio fx-300ES Plus to be ideal for ACT prep.

3. Four-function calculators

These are the simplest calculators, covering addition, subtraction, multiplication, and division. While allowed, they are not always the best choice because they lack features like trigonometry or exponents, which show up in ACT Math. Still, for students who prefer simplicity and speed, a basic four-function calculator works perfectly.

Desmos on the Digital ACT: What's Different From Classroom Desmos?

Students taking the Digital ACT can use the Desmos graphing calculator built into the testing platform during the Math section, or bring their own approved handheld calculator. Paper-based ACT test-takers must bring their own approved calculator because the built-in Desmos option is only available in the digital testing environment.

The ACT version of Desmos is also different from the standard classroom version. Certain features are disabled, including images, folders, notes, some advanced trigonometric and statistical functions, and audio. The default angle mode is degrees rather than radians.

If you normally use Desmos in class, practice with the testing version before test day so the interface and available functions are familiar.

For a broader look at the digital testing experience, see our guide to the Digital ACT format.
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Full list of approved calculators for the ACT

ACT.org states you may use any four-function, scientific, or graphing calculator as long as it is not on the prohibited list. Some examples of approved models include:

Important note: Some calculators are allowed only if modified. For example:

• Stored programs and documents: Any programs or documents stored on the calculator must be completely removed before the test. Disabling or hiding them is not enough.
• Calculators with paper tape: remove the tape
• Calculators with sound: turn off the sound
• Calculators with infrared ports: cover the port with opaque tape
• Calculators with power cords: remove the cords; only battery-powered calculators are permitted
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Which Calculator Should You Actually Buy?

There is no single calculator that every ACT student needs. The right choice depends on your budget, familiarity with the device, and how much you use a calculator during Math.

Most popular overall: TI-84 Plus CE

The TI-84 Plus CE typically costs around 130-150. It has a color screen, is non-CAS, and is widely used in high school math classrooms. If you already know how to use one, its familiar interface can make it a practical ACT choice.

Best budget graphing option: Casio fx-9750GIII

The Casio fx-9750GIII typically costs around $60 and provides graphing functionality at a substantially lower price than the TI-84 Plus CE. It is an approved non-CAS option for students who want a graphing calculator without spending as much.

Best budget scientific options: TI-30X IIS or Casio fx-300ES Plus

For students who prefer a scientific calculator, the TI-30X IIS typically costs around $15, while the Casio fx-300ES Plus is around $12. Both are inexpensive options and can also work well as backup calculators.

The most important rule

The best ACT calculator is usually the one you already know how to use. Buying an unfamiliar calculator shortly before the test can create unnecessary problems with button layouts, functions, and input speed. Choose early and practice with the same model you plan to use on test day.
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Prohibited calculators for the ACT exam

Certain calculators are not allowed because they offer unfair advantages or pose security risks. These include calculators with built-in Computer Algebra Systems (CAS) and those that can connect to external devices.

Other devices not allowed:

• Tablets, laptops, and handheld computers.
• Calculator apps on phones.
• Electronic writing pads or pen-input devices.
• Calculators with QWERTY keyboards.

If you bring one of these by mistake, testing staff can confiscate it and even dismiss you from the exam. So double-check before you pick the calculator for the test.
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Best calculator usage tips for ACT test day

Having the right calculator is not enough—you also need to know how to use it under test conditions. Here are some practical tips to help you stay prepared:

Bring your own: ACT staff will not provide calculators, so you must bring one that is on the approved list. If you forget, you will have to take the math test without one, which puts you at a big disadvantage.

Check batteries: Make sure your calculator is fully charged or has fresh batteries the night before the exam. Many students panic when their device dies mid-test. Bringing a backup calculator or extra batteries gives you peace of mind.

Practice with the same calculator: Switching calculators at the last minute can cost you time. If you prepare with one model but use a different one on test day, the button layout or functions may feel unfamiliar. Stick to the same calculator for all practice and the actual exam.

Use calculators strategically: Not every problem requires a calculator. Basic arithmetic—like adding fractions or multiplying simple numbers—is often faster by hand. Save your calculator for longer equations, graphs, or multi-step problems where accuracy matters. For example, if a problem involves a simple calculation you can do mentally in a few seconds, entering it into the calculator may take longer than solving it directly. 

Know the limits: Every ACT math problem is designed to be solved without a calculator. Over-relying on it can actually slow you down if you punch in numbers for things you could do quickly in your head. Train yourself to recognize when the calculator is truly helpful.

Avoid This Common Calculator Input Mistake

One common source of calculator errors is entering negative numbers incorrectly when using exponents.

(-3)² = 9, because the parentheses tell the calculator to square the entire negative number.

-3² = -9, because the calculator squares 3 first and then applies the negative sign.

The difference becomes important when substituting negative values into equations. For example, for f(x) = 2x² - 5x + 3, finding f(-2) requires entering:

2(-2)² - 5(-2) + 3

The parentheses around -2 ensure that the negative value is squared correctly.

The fix is simple: always put negative numbers in parentheses before applying an exponent, and quickly check your calculator input before pressing Enter.
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Common misconceptions about the ACT calculator policy

You may often hear conflicting advice about calculator rules, which can create confusion. Let’s clear up the most common myths so you know exactly what to expect.

• “Any graphing calculator is allowed”

Only non-CAS (Computer Algebra System) models are permitted. For example, the TI-Nspire (non-CAS) is approved, but the TI-Nspire CAS is banned. CAS calculators can solve equations symbolically, which the ACT prohibits. Always double-check your exact model.

• “Smartphone calculator apps are permitted” 

Phones, tablets, and laptops with calculator apps are strictly prohibited. If you bring one out during the test, you risk dismissal and score cancellation. Only handheld, approved calculators are acceptable.

• “Calculators are allowed on all sections” 

They are only allowed on the math section. For English, Reading, and Science, calculators are not needed and not permitted. 

• “You can share calculators during the test”  

Sharing is not allowed under any circumstances. If your calculator stops working, you cannot borrow one from another student. The safest plan is to bring a reliable calculator and a backup with fresh batteries.

• “Proctors provide calculators if yours fails” 

ACT proctors do not provide calculators. If your device dies mid-test and you do not have a backup, you will have to finish the math section without one.

• The calculator rules are the same for the paper and digital ACT.

Not exactly. Digital ACT test-takers can use the Desmos graphing calculator built into the testing platform during Math or bring their own approved handheld calculator. Paper ACT test-takers must bring their own approved calculator. The calculator options therefore differ depending on the testing format.
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How EdisonOS helps

For tutors, keeping up with every ACT calculator rule and making sure students practice under the right conditions can be challenging. EdisonOS streamlines this by combining guidance, practice, and performance tracking in one platform.

• Clear calculator policy resources:

EdisonOS provides easy-to-understand materials that outline which calculators are allowed, which ones require modifications, and which are prohibited—so you never have to double-check the ACT website mid-session.

• Realistic test-day simulations: 

Students can practice in a digital ACT environment and build familiarity with the Math section, pacing, and on-screen testing experience before test day. This builds familiarity with both the rules and the pacing of the math section.

• Integrated performance tracking:

Integrated performance tracking: Students' practice performance is recorded so tutors can track accuracy, pacing, and progress across practice sessions and use that data to guide instruction. 

By simulating ACT conditions, EdisonOS ensures students walk into test day already comfortable with their calculator and the rules around it.

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The bottom line

The ACT calculator policy is straightforward once you know the rules. Choose an approved calculator, make sure it meets ACT's modification requirements, and practice with the same device you plan to use on test day.

If you're taking the Digital ACT, remember that you also have access to the testing platform's built-in Desmos calculator during Math. Paper test-takers must bring their own approved handheld calculator.

Whichever option you choose, familiarity matters. Practice with your calculator well before test day so you can focus on solving problems rather than figuring out the device.

Book a demo today.