Great news–you’re allowed to use a calculator on the Math section of the ACT!

But be aware, the company has a strict policy on which *types* of calculators are okay and which aren’t. If you arrive at the test center with a prohibited calculator, the proctor will confiscate it, and you’ll have to complete the whole math section by hand. Worse yet, if you’re spotted with a prohibited calculator partway through the Math section, you may be dismissed from the test and have your scores canceled.

Luckily, it’s not hard to make sure that nothing like that ever happens to you. Just follow these guidelines to pick an approved calculator that gives you exactly the support you need.

ACT Inc. tells us that:

*“Examinees may use any 4-function, scientific, or graphing calculator, as long as it is not on the prohibited list and it is modified, if needed.”*

But what’s the Prohibited List? (I hear you cry). It’s right here:

**Calculators with built-in or downloaded computer algebra system functionality are all prohibited. That includes:**

- All model numbers that begin with TI-89 or TI-92
- TI-Nspire CAS

*Note: The TI-Nspire (non-CAS) is permitted.*

- HP Prime
- HP 48GII
- All model numbers that begin with HP 40G, HP 49G, or HP 50G

- fx-CP400 (ClassPad 400)
- ClassPad 300 or ClassPad 330
- Algebra fx 2.0
- All model numbers that begin with CFX-9970G

- Handheld, tablet, and laptop computers (including PDAs) are prohibited.
- Electronic writing pads and pen-input devices are not okay (
*Note: The Sharp EL 9600 is permitted).* - Calculators that are built into cell phones or any other electronic communication devices are not allowed.
- Calculators with QWERTY-format letter keys are prohibited (This does not apply to calculators that are provided in a secure test delivery platform).
- Letter keys not in QWERTY format are fine.
- Calculators with paper tape are fine as long as you remove the tape.
- Calculators that make noise are okay as long as you turn off the sound.
- Calculators with an infrared data port are fine if you completely cover the infrared data port with heavy opaque material such as duct tape or electrician’s tape. These calculators include the Hewlett-Packard HP 38G series, HP 39G series, and HP 48G.
- No power cords are allowed.

As part of your preparation for the ACT, you’ll want to choose a permitted calculator and give yourself time to get to know it well. Use it for school and homework. The best calculator for the ACT is no help to you if you’re struggling to figure out how to make it work.

Bring a backup calculator plus fresh batteries for both, just in case.

Here, in no particular order, are five calculators that ACT experts love. It’s far from a complete list, but these are my genuine recommendations.

This versatile, intuitive calculator is many people’s top choice for the ACT. The mathematical functions are easy to reach–not buried deep down in the menus–so you can find what you need quickly. It has a high-resolution LCD display and plenty of memory. It’s specifically approved for use on the ACT.

This is one of the most powerful calculators permitted on the ACT. It gives you answers back in both fraction and rationalized format, so you end up with a nice, clear 10/19 rather than a mess like 0.5882352.The super-clear screen measures 2.8 inches on the diagonal, with a full-color backlit display.

This may be the most eye-friendly calculator out there. It has a great 3.5-inch color screen with a resolution of 125 DPI. If you don’t have much time to get to know your new calculator, the TI-Nspire is a good choice because it’s so intuitive. It’s also exceptionally thin and light, and it holds its charge really well. Approved for use on the ACT.

This is a down-to-earth scientific calculator that still does exactly what you need it to in the test room. Its 240 functions support basic calculation, scientific function calculation, and statistical calculation. The Aibecy is specifically approved for use on the ACT.

The HP39GS is my favorite budget pick. It does everything you need it to do on the ACT. There’s a split-screen view, plus you can also switch among symbolic, numeric, and graphic options. The HP39GS is great for use on the ACT as long as you cover the infrared data port with something opaque like electrician’s tape.

There are lots of other good ACT calculators out there. If you have a different one that you’d like to use, ask yourself these three simple questions to determine whether it’s permitted:

- Is my calculator a four-function, scientific, or graphing calculator? (If so, great! Continue to Question #2).
- Is my calculator built into a phone, laptop, or other electronic device? (If not, you’re doing fine. Continue to Question #3).
- Is my calculator on the Prohibited list above, or does it break any of the rules in “Other Important Notes”? (If the answer is no, you’re golden).

- Be sure to plan ahead and bring your own calculator. The testing center won’t lend you one, and students aren’t allowed to share.

- You can use your calculator only on the Math section of the ACT. It needs to be stowed away during Reading, English, and Science.

- It’s nice to have a calculator model with an entry line, so you can glance down as you go and check for careless mistakes.