02/25/2026
Calculators! I have a lot to say about this topic. So, let's jump right in and investigate the most updated SAT Calculator policy – as of August 2025 – and why I recommend bringing a TI-84 Plus graphing calculator to the exam.
First, an online graphing calculator is available to use during the SAT. It's called 'Desmos', and yes, it's great at a LOT of things. If you haven't used it before, its capabilities might surprise you. And even if you HAVE used it, chances are you haven't used it to its fullest capacity. All of Module 3 of my course Streamlined SAT Math is dedicated to learning how to use Desmos to do a variety of things much faster and more accurately than without it. In many cases, it even makes a question possible to do – much more math knowledge would be required to answer that question without it. Practice with the exact version of Desmos that's built in to the SAT: https://www.desmos.com/testing/cb-sat-ap/graphing.
Here's where it gets even better:
You are also allowed to bring a handheld calculator to the test, to use in addition to Desmos. The calculator you bring with you must be an approved type. Below is my summary of what is allowed and what is not allowed, with some clarification and commentary. (You can read the full policy without my commentary here, if you want: https://satsuite.collegeboard.org/sat/what-to-bring-do/calculator-policy)
CAS calculators are not allowed. 'CAS' stands for 'computer algebra system', and these calculators will have the 'CAS' designation in the model name. These are calculators that solve equations and manipulate algebraic expressions symbolically. For example, if you type in 'x+x', it will produce the output '2x'. And if you ask it to solve the equation 'x²-8=0', it will produce the solutions 'x=2√2, x=-2√2. Non-CAS calculators only output numbers as decimals or fractions, not with other math symbols.
Non-CAS graphing calculators are allowed. The TI-84 Plus is in this category. It can't solve equations symbolically, but it CAN solve them numerically. It can't simplify expressions symbolically, either – it will instead output a decimal or fraction. On the TI-84 Plus, if you type 'x+x', it will not answer '2x'. It will instead take the number you have stored as 'x' and add it to itself. The output will a number that is double the value that you've stored as 'x'. Solutions to equations will be numbers in the form of decimals or fractions, without the use of other math symbols, such as √ or π.
For calculators that hold programs, there is this requirement: "You must remove programs that have algebra functionality (e.g., solving equations, expanding algebraic expressions, factoring algebraic expressions, etc.) from your calculator." These would be programs that can do the things that the CAS calculator can do, so remove those. Keep in mind that numerical solving is allowed – it's a built-in function after all – so programs that do numerical solving do not need to be removed. Proctors are not instructed to require students to clear all stored programs. It is my recommendation that if you are asked to clear out the programs, or 'clear the RAM', you should present a printed copy of the calculator policy to show that this is not required. It's very unlikely this will happen, but you never know what personal agenda an individual proctor might have.
Students enrolled in my course Streamlined SAT Math receive many programs for the TI-84 Plus calculator. These programs don't have 'algebra functionality', meaning that they don't do the things described above, that the CAS calculators can do. Don't worry, though, you don't need a symbolic equation solver, because the built-in numeric equation solver is just as useful. Desmos solves equations numerically, too. And if you learn how, you can get either the TI-84 Plus or Desmos to identify equivalent expressions – numerically, of course!
If your calculator can store documents, you are required to remove them. You can't have textbooks or notes stored, for reference. Programs are not documents.
Just a note: Students have reported to me for years that the proctor only checks the model of the calculator to see that it is allowed – nothing else. While this is just anecdotal evidence, it suggests that you aren't going to get into it with a proctor over whether or not a particular program has a prohibited capability. There just isn't time for that, and proctors are probably not knowledgeable in the workings of every model of calculator that might be brought to the test. Still, play by the rules.
Scientific and four function calculators are allowed, too, but ... don't bother. They won't give you any advantage. The TI-84 Plus is the best option to achieve things that Desmos won't do.
I'm just going to say it: If you aren't using a TI-84 Plus graphing calculator, you are leaving points on the table. Plain and simple. It's the best calculator to supplement what Desmos does: it's user friendly, has loads of built-in capabilities, and it runs all of the programs available in my online course. I require students to have this calculator when they sign up for tutoring sessions with me.
All models of the TI-84 Plus are approved for use on the SAT. Which model should you get? I address that in the first FAQ question here: https://www.xfactorytestprep.com/links. If buying a new one isn't in your budget, check Ebay or similar for a used one. Happy testing!
