What this calculator does not do
This is a small demonstration project, not a scientific calculator, and it is more useful to say so directly than to let anyone discover it by trying. It does four-function arithmetic, square root, squaring and factorial, with a memory register and a short history. Everything below is something it genuinely does not do, verified by looking for the feature in the source and not finding it. None of these are bugs; they are the edges of what was built.
No keyboard input
Every button is wired with an inline click handler and there is no key listener anywhere in the page's JavaScript. Typing digits does nothing; you have to click. On a desktop with a numeric keypad sitting right there, this is the limitation people notice first, and it is a real gap rather than a deliberate choice.
Nothing is saved
The page uses no browser storage of any kind. There is no local storage, no session storage, no database and no cookie. The working value, the memory register and both histories live in memory for the lifetime of the tab, and a reload starts from zero with an empty history.
This is the same property that makes the calculator private, so it cuts both ways: nothing is stored anywhere, which also means nothing survives. There is no service worker and no manifest either, so it is not installable and it will not load without a connection, even though every calculation after the first load runs entirely offline.
No operator precedence and no parentheses
The calculator evaluates strictly left to right as you press keys, the way a pocket calculator does. There is no expression parser, no precedence handling and no bracket keys. Entering two, then plus, then three, then times, then four gives twenty, because the addition is completed when the multiply key is pressed. A calculator that respected precedence would give fourteen. Neither is wrong; they are different machines, and this one is the pocket kind.
There is also no key for changing sign and no backspace. A mistyped digit has to be cleared and re-entered.
No scientific functions
The engine contains no trigonometry, no logarithms, no exponentials beyond raising the display value to a power, and no constants. What it does contain is listed in full on the operations page, and that list is complete rather than representative.
- No sine, cosine or tangent, and no inverse or hyperbolic forms.
- No natural or base-ten logarithm.
- No pi or e.
- No arbitrary root; square root is the only one.
- No arbitrary exponent from the keypad. The engine's power function accepts any exponent, but the only button that calls it passes two.
Where the numbers stop
Ordinary arithmetic is 64-bit floating point, which carries about fifteen to seventeen significant digits and reaches roughly ten to the power of 308. Beyond that a result becomes infinity, and it stays infinity through every operation that follows. Precision is the more common limit in practice: a tenth plus a fifth does not give exactly three tenths, for the same reason it does not in any other floating point calculator.
Factorial stops much earlier, at 20. That is not a floating point limit but a deliberate one, explained on the factorial page. There is no arbitrary-precision mode and no BigInt anywhere in the exported surface, as the boundary page describes.
Two functions with no button
The WebAssembly module exports a percentage function and a compound interest function that no control on the page calls. They are reachable only by importing the module and calling them yourself. The percentage and compound interest pages document both, including how to get the same answers using the keys that do exist.
Questions and answers
Can I type numbers with my keyboard?
No. Every button uses a click handler and there is no key listener in the page's JavaScript, so input is by clicking only.
Does the calculator respect operator precedence?
No. It evaluates left to right as keys are pressed, like a pocket calculator. Two plus three times four gives twenty, not fourteen. There are no parentheses and no expression parser.
Does it remember my calculations between visits?
No. The page uses no local storage, session storage, database or cookies. Everything lives in memory for the lifetime of the tab and a reload starts from zero.
Does it work offline?
Calculations run entirely in the browser once loaded, but there is no service worker and no manifest, so the initial page load still needs a connection and the calculator cannot be installed.
Are there trigonometric or logarithmic functions?
No. The engine has no sine, cosine, tangent, logarithm or constants. Square root, squaring and factorial are the only operations beyond the four arithmetic operators.