Scientific Calculator
A full scientific calculator in your browser: trig, log, ln, powers and roots with a live result — no eval, no server, no tracking.
Type with the keypad or your keyboard. Implicit multiplication works (2π, 3(4+1)); % divides by 100; DEG/RAD switches trigonometric units.
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Tap the keypad or type an expression with your keyboard.
- 2Toggle DEG/RAD for trigonometric functions as needed.
- 3Press = to commit the previewed result, then keep calculating on it.
Scientific Calculator
A keypad plus a typeable expression line: sin, cos, tan (DEG/RAD), log₁₀, ln, square root, squares, arbitrary powers, parentheses, π and e. The result preview updates as you type, and = folds it back into the expression for chained calculations.
Expressions are parsed by a hand-written recursive-descent evaluator built for this site — JavaScript's eval and Function constructor are never used, and nothing is sent anywhere. Implicit multiplication (2π, 3(4+1)) works out of the box.
Frequently asked questions
How are the expressions evaluated?
By a small tokenizer and recursive-descent parser written into the page: numbers, constants, functions, parentheses, unary minus, postfix % and x², right-associative powers, and implicit multiplication between adjacent values. Invalid input simply shows an error instead of executing anything.
How do I get a tangent of 45 degrees?
Leave the DEG toggle active (it is the default), press tan, then 45 and =. For radians — e.g. tan(π/4) — switch to RAD and type tan(π/4) directly.
Why is my result shown with limited digits?
Results are rounded to 12 significant digits to hide floating-point noise such as 0.30000000000000004. Precision beyond 12 digits is rarely meaningful on binary floating-point hardware anyway.
Related tools
Percentage Calculator
Three percentage problems in one live tool: X% of Y, X is what percent of Y, and the percent change between two values.
All tools →
Binary Converter
Convert between decimal, hexadecimal, octal and binary in one live grid — supports arbitrarily large integers, grouping for readability.
All tools →
EMI Calculator
Compute the fixed monthly EMI for any loan — principal, rate and tenure in, total interest and total repayment out, instantly.
All tools →
Roman Numeral Converter
Convert numbers to Roman numerals and back, in both directions at once — with strict classical validation of subtractive notation.
All tools →
Embed this tool
Put this tool on your own site with one line — it runs entirely in the visitor's browser.
<iframe src="https://zoyku.com/en/tools/scientific-calculator?embed=1" width="100%" height="640" style="border:0;border-radius:16px" title="Zoyku — scientific-calculator" loading="lazy"></iframe>