Scientific Calculator
Full scientific calculator with trig, logs, powers, memory and history
⌨️ Keyboard supported — numbers, operators, Enter (=), Backspace (⌫), Escape (AC)
Results & Details
// History
// Function Reference
How to Use the Scientific Calculator
Click buttons or type on your keyboard. Use the DEG/RAD toggle to switch between degrees and radians for trigonometric functions. Press 2nd to access inverse trig functions (arcsin, arccos, arctan). All calculations are shown in the history panel and can be clicked to recall the result.
Order of Operations
This calculator respects standard mathematical order of operations (PEMDAS/BODMAS): Parentheses first, then Exponents, then Multiplication and Division (left to right), then Addition and Subtraction (left to right). Use parentheses to override this where needed.
Memory Functions
MS — store current value in memory. MR — recall memory value. M+ — add current value to memory. M− — subtract current value from memory. MC — clear memory. A blue "M" indicator appears when memory holds a value.
From the Blog
Getting Right Answers From a Scientific Calculator
Built and verified by Andrius R. · Updated June 2026
A scientific calculator is never wrong — but it ruthlessly answers the question you actually typed, which is often not the one you meant. The handful of traps below account for the vast majority of "the calculator is broken" moments, in classrooms and engineering offices alike.
Trap 1: degrees vs radians (the classic)
sin(30) in degree mode = 0.5. sin(30) in radian mode = −0.988 — because 30 radians is about 4¾ full circles plus a bit. Neither answer is wrong; the mode decides the question.
Convention: geometry and everyday problems use degrees; calculus, physics formulas and programming languages default to radians (180° = π rad). The habit that prevents the trap: check the mode indicator before any trig, and sanity-check with a known value — sin of a small angle should be small and positive; if sin(30) comes back negative, you're in the wrong mode, not the wrong universe.
Trap 2: order of operations and the viral expression
Calculators apply strict precedence — parentheses, exponents, multiplication/division left-to-right, addition/subtraction — which is why −3² returns −9 (the square binds before the negation; type (−3)² for +9), and why the internet's favorite bait, 6 ÷ 2(1+2), splits humanity: strict left-to-right reading gives 9, while treating 2(1+2) as one implicit-multiplication unit gives 1. Different calculator models genuinely disagree, which is the real lesson: the expression is badly written, not deep. Professionals never write it — they add parentheses until no reader (human or silicon) can misparse. When in doubt, over-parenthesize; brackets are free.
Trap 3: scientific notation and the limits of precision
An answer like 2.5E−4 means 2.5 × 10⁻⁴ = 0.00025 — the E is an exponent, not an error (and not e ≈ 2.718, a separate key entirely). Underneath, calculators carry ~10–15 significant digits of floating-point, which is why 0.1 + 0.2 can display as 0.30000000000000004 in many systems: 0.1 has no exact binary representation, the same way 1/3 has no exact decimal one. Everyday consequence: tiny residues like 1E−13 after a computation are rounding dust, not discoveries — and money math in serious software is done in integer cents for exactly this reason.
Habits that catch errors before they ship
- Estimate first: 47 × 312 should be near 15,000 (50 × 300). A magnitude check catches mistyped digits and slipped decimal points — the two dominant real-world errors — instantly.
- Mind log vs ln: log is base-10, ln is base-e; log(100) = 2 but ln(100) ≈ 4.605. Chemistry's pH uses log; growth and calculus use ln.
- Use memory/ANS instead of retyping: every manual re-entry of an intermediate result is a fresh chance to transpose digits — and rounding intermediate values then continuing is how multi-step answers drift off the mark sheet. Round once, at the end.
- Respect the inverse-trig range: sin⁻¹ only returns −90° to 90°, so equations with obtuse-angle solutions have a second answer the calculator won't volunteer (180° − the one it gave). The triangle that "doesn't work" usually lives there.
What the buttons are actually for
The keys beyond arithmetic each anchor a field: trig runs geometry, navigation, waves and anything that rotates; logarithms tame quantities spanning many magnitudes (earthquakes, decibels, pH, compound growth — see the compound interest calculator for log's financial day job); exponentials model growth and decay; factorial and the nCr/nPr pair count arrangements for probability. A scientific calculator is less a machine than a tour of applied math's greatest hits — knowing when each key applies is the actual skill, and the worked examples across this site are that skill in practice.
// Chaining
Click a result in history to load it into the display, then continue calculating from there.
// Degrees vs Radians
sin(90°) = 1 in DEG mode. In RAD mode, sin(π/2) = 1. Always check your angle mode before trig calculations.
// Memory Tip
Use M+ to accumulate a running total — add each result to memory and read the final sum with MR.
// Keyboard Shortcuts
Enter = equals, Escape = AC, Backspace = delete, ^ = power, % = percent.