The best ACT calculator is one you already know well and that's on the approved list, commonly the TI-84 Plus. Familiarity matters more than features. A calculator is allowed on the entire Math section, but the right habits matter more than the model.
Check the approved list first
The ACT permits most graphing and scientific calculators but bans some models and any with computer-algebra systems (CAS), like the TI-89. Always verify your model against the current official ACT calculator policy before test day so there are no surprises.
Popular reliable choices
The TI-84 Plus family is the most common, well-supported, allowed, and familiar to most students and teachers. A solid scientific calculator works too if you don't need graphing. The "best" one is the one you've practiced with.
Don't over-rely on it
Many ACT questions are faster by hand or by plugging in answer choices. Reaching for the calculator on every problem wastes time. Build mental and paper math so the calculator is a tool, not a crutch.
Know your shortcuts
Learn graphing, solving, and table features to check work quickly, but practice them in advance. Fumbling with menus on test day costs the time you were trying to save.
Bring backups
Fresh batteries and, ideally, a spare calculator prevent a test-day disaster. Add this to your week-before checklist.
Practice with your test-day calculator
Use the exact calculator you'll bring during all practice on thirty-six so it's second nature. For the bigger picture, see how to improve your ACT Math score.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
This article offers general ACT prep guidance. The ACT can change from year to year, including its format, scoring, policies, test dates, and fees, so always confirm the latest details on the official ACT website at act.org before you make decisions. ACT® is a registered trademark of ACT, Inc. thirty-six is not affiliated with, endorsed by, or sponsored by ACT.