It reads what you type, not just what you tap
The input is a real expression, so you can type 2*sin(pi/4)^2 straight in and press Enter. Brackets nest, precedence works the way it does on paper, and implicit multiplication is understood — 2x, 3(4+1) and 2pi all mean what they look like.
One detail that trips up most calculators: exponents are right-associative, so 2^3^2 is 2⁹ = 512, not 8² = 64. And -2^2 is −4, because the minus applies after the power. Both match standard mathematical convention.
The tape is the feature
Every result is kept, and clicking a past line drops it back into the input so you can edit and re-run it. ans refers to the last answer and composes like any value — ans*2, sqrt(ans).
The tape lives in your browser's local storage, so it survives a refresh and a closed tab. Nothing about it leaves your machine.
Degrees and radians
The angle switch changes both directions: in degree mode sin(30) is 0.5 and asin(0.5) is 30. Getting this wrong is the single most common source of wrong trigonometry answers, so the current mode is always visible rather than hidden in a menu.
Frequently asked questions
Why does 0.1 + 0.2 not give exactly 0.3?
Because binary floating point cannot represent 0.1 exactly — this is true of every calculator built on a computer. The display rounds to the decimal places you choose, which hides the artefact; set decimals to 'max' to see it.
Is anything uploaded?
No. Nothing you type is sent anywhere, and the history stays in this browser.
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