Scientific Calculator
A real expression calculator with a safe parser.
Scientific Calculator evaluates full expressions with trigonometry, logarithms, powers, roots, factorials, constants and memory, and keeps a visible history you can reuse. It uses a purpose-built recursive-descent parser — never eval or new Function — so a pasted expression cannot execute code in your browser.
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Runs entirely on your device. No file or text you enter here is uploaded. How to verify it.
How to use Scientific Calculator
- Type an expression, or use the keypad.
- Switch between degrees and radians as needed.
- Press equals; the result and the expression stay in the history.
Questions about Scientific Calculator
Why does a safe parser matter for a calculator?
The lazy way to evaluate
2+3*4 is eval(), which will happily run any JavaScript in the same string. If a page ever renders an expression from a URL or a paste, that becomes code execution. This calculator tokenises and parses instead, so the worst input can do is produce an error.Which functions are supported?
sin, cos, tan and their inverses and hyperbolic forms, log, ln, log2, exp, sqrt, cbrt, nth root, abs, floor, ceil, round, factorial, permutations, combinations, modulo, and the constants π and e.
Degrees or radians?
Both, with a clearly marked DEG/RAD toggle that starts in degrees on every load. The current mode is always shown next to the display, because a silent radians mode is the source of most wrong trigonometry answers.
Does it replace a graphing calculator?
No. It evaluates expressions and keeps a history, but it does not plot functions, solve symbolically or handle matrices. For a parabola the Quadratic Equation Solver draws one; beyond that you want a computer algebra system rather than a web page.
How long does the history keep my calculations?
The last 25 entries, for as long as the tab is open. They are held in the page and never sent anywhere, and a refresh clears them — deliberate, because a calculator history can expose salaries, doses and prices to anyone who picks up the device.
Is Scientific Calculator really free, with no limits?
Yes. There is no account, no daily cap, no file-size tier and no watermark, because there is no server cost to recover. The site is funded by clearly disclosed partner recommendations on the Partners page, never by metering the tools.
Are my files or text uploaded when I use Scientific Calculator?
No. Everything is processed by JavaScript running in your browser, on your device. You can verify it: open your browser's developer tools, switch to the Network tab, and use the tool. You will see no request carrying your data — because there is nowhere for it to go.