Desmos SAT Calculator: How to Use It on the Digital SAT

Sriram Venkataraman

07/10/2026

5 min read

Yes, you can use Desmos on the SAT. The Digital SAT has a Desmos calculator built into Bluebook, College Board’s testing app, and it has a graphing mode and a scientific mode that you can switch between at any point in the Math section. You can also bring your own approved handheld calculator instead (College Board calculator policy, 2026).

That short answer hides the details that matter on test day: when the calculator is available, which handheld calculators are banned, what happens if yours stops working, and how to get comfortable with Desmos before you sit the test. Every policy point below comes from College Board’s own pages, read in September 2026.

What is the Desmos calculator on the SAT?

Desmos is the calculator that comes built into Bluebook, the app the Digital SAT runs in. College Board describes it plainly: “Bluebook contains an embedded Desmos calculator with two options—graphing or scientific” (College Board calculator policy, 2026).

It is not only on the SAT. According to Bluebook’s own tools page, you get a Desmos calculator “on the SAT, PSAT-related assessments, and certain AP Exams,” and you can drag it anywhere on the screen so it does not cover the question (Bluebook testing tools, College Board, 2026). The same page confirms that a reference sheet with commonly used formulas appears on every test with math questions, so you do not have to memorise those formulas to use the calculator well.

When can you use the calculator on the Digital SAT?

Only in the Math section, and throughout it. College Board says students “can toggle between scientific and graphing options at any point in the Math section” (College Board calculator policy, 2026). The Math section is two 35-minute modules with 44 questions in total (College Board, SAT structure, 2026).

The Reading and Writing section is different. You may not use a calculator there, and if you brought your own, it has to stay under your desk during those modules.

Should you use Desmos in Bluebook or bring your own calculator?

College Board’s advice is to use the calculator you know best: “We encourage you to use the calculator that is most familiar to you on test day.” If you already know Desmos, it adds that “the embedded version is a good choice.” A handheld calculator is not required. Here is how the two options compare, point by point:

Sources for every cell: the College Board calculator policy and the Bluebook testing tools page, both read in September 2026.

Which calculators are not allowed on the SAT?

The rule that catches most students is the one on CAS. “Only non-CAS (computer algebra system) calculators are allowed,” and College Board lists the features that make a device ineligible (College Board calculator policy, 2026):

• built-in CAS functionality, or apps, menus or programs that do symbolic algebra
• a QWERTY keyboard
• wireless internet, Bluetooth or cellular connectivity
• a built-in camera or audio or video recording
• tablets and laptop computers
• electronic writing pads
• calculator apps on a phone
• paper tape

If you are unsure whether your model qualifies, check it against that page well before test day, not on the morning of the test. Using a calculator to share information or to take test content out of the room gets you dismissed and your scores cancelled.

What happens if your calculator stops working during the test?

You are not stuck. College Board’s policy says: “If your calculator fails during testing and you have no backup, you can continue testing using the built-in Desmos calculator.” That is also the best argument for learning Desmos even if you plan to bring your own calculator: it is your fallback, and the moment you need it is the worst moment to meet it for the first time.

How do you get ready to use Desmos on the SAT?

College Board suggests three ways to learn the embedded calculator: explore the Math section in Bluebook’s test preview, take a practice test in the Bluebook app, or use the scientific and graphing calculators on the Desmos website. If you bring your own calculator instead, its advice is to bring one you already know and practise with that same calculator.

Two habits make the practice count:

• Practise under timed conditions. Knowing where the buttons are is not the same as using them with 35 minutes on the clock.
• Decide when not to use it. College Board notes that the Math section “includes some questions where it’s better not to use a calculator, even though you’re allowed to,” and suggests getting your thoughts down on scratch paper first.

When you are ready to try it under real timing, take a free SAT practice test. Once you have a score, estimate your SAT score from your section results to see where you stand.

For more on how Bluebook practice compares with test day, read our guide to Digital SAT practice in Bluebook versus the real test. If Math is your weaker section, the SAT Math practice blueprint sets out a plan from fundamentals upward.