What is Desmos?
4 min read · updated 2026-09-01
Desmos is the graphing calculator built into the Bluebook app for the entire Digital SAT math section. Students who master it solve in seconds what used to take minutes by hand.
What it does
Desmos graphs equations instantly: type an equation and see the curve, find intersections by tapping, solve systems visually, and test answer choices by plotting them. Many Digital SAT algebra questions that look algebraic are solved faster by graphing both sides.
Why it changes preparation
On the paper SAT, graphing questions tested by-hand sketching. On the Digital SAT, the skill is knowing what to type into Desmos and how to read the result. Students who practise in Desmos specifically (it is also free at desmos.com) gain a real pacing advantage across the math section.
The three Desmos moves worth drilling
- ✓ Graph both sides of an equation and tap the intersection: solves systems and 'how many solutions' questions
- ✓ Plot a line through a point to test 'which point lies on the line' answers
- ✓ Use sliders for constants in transformation questions
FAQs
Can students use their own calculator too?＋
Yes, Bluebook allows a personal calculator alongside Desmos, but many students find Desmos faster for graphing questions. Practice decides which to use per question type.
Is Desmos allowed on school exams too?＋
For the Digital SAT yes, and Desmos is also approved in several state and international exams. Check your specific exam's calculator policy.
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