🧮 Calculator
Basic & Scientific Calculator
A complete calculator with two modes: a clean basic keypad and a full scientific set including trigonometry, logarithms, powers, roots, factorials and the constants π and e.
What this calculator supports
- Arithmetic: addition, subtraction, multiplication, division, percent and factorials
- Powers: x² and xʸ with right-associative exponents
- Roots: square root and cube root
- Trigonometry: sin, cos, tan plus their inverses, in degrees or radians
- Logarithms: natural log (ln) and base-10 log
- Constants: π and e (Euler's number)
Untrusted input is never executed as code — expressions are parsed with a small shunting-yard evaluator, so the calculator is safe to use in a shared browser.
Worked example
To find 12.5% of 840, enter 840 × 12.5 ÷ 100 and you get 105. For something like (3 + 4) × 5, the brackets force the addition first, giving 35 rather than the 23 you would get without them.
Everyday uses
- Everyday arithmetic and quick percentages
- Homework in algebra, trigonometry and statistics
- Powers, roots, logarithms and factorials
- Checking totals before you commit to a figure
- Any calculation where no unit is involved
Frequently asked questions
Addition, subtraction, multiplication and division, plus powers, square roots, trigonometric functions, logarithms, factorials and constants such as π.
Yes. Powers are applied first, then multiplication and division, then addition and subtraction, with brackets overriding the order.
Yes. Typing digits and operators works, and Enter evaluates the expression.
No. The calculation runs entirely in your browser; nothing is transmitted or saved.
More worked examples
- Order of operations matters: 2 + 3 × 4 is 14, not 20, because multiplication happens before addition.
- A 15 percent increase on 80 is 92, since 80 × 1.15 = 92.
- Two to the power of ten is 1,024.
- In binary floating point, 0.1 + 0.2 gives 0.30000000000000004, though most calculators round the display to 0.3.
Quick reference
| Expression | Result |
|---|---|
| 2^10 | 1,024 |
| 10^6 | 1,000,000 |
| √144 | 12 |
| 15% of 80 | 12 |
| 80 increased by 15% | 92 |
| 5! | 120 |
Common mistakes to avoid
- Ignoring the order of operations and reading the expression left to right.
- Typing percentages without converting them to decimals, so 20 percent becomes 20 rather than 0.2.
- Using degrees when the function expects radians, or the reverse, which gives a plausible but wrong answer for trigonometry.
- Trusting every displayed digit of a floating-point result. Binary arithmetic cannot represent most decimal fractions exactly.
Further questions
Brackets first, then powers and roots, then multiplication and division, then addition and subtraction. An acronym such as BODMAS or PEMDAS is a memory aid for the same rule.
Because binary floating point cannot store those decimal fractions exactly, so tiny rounding errors appear far down the decimal places.
Powers, roots, logarithms, exponentials and trigonometric functions, along with constants such as pi.
No. Every calculation runs locally in your browser, and nothing you type is transmitted or stored on a server.
Sources and standards
The arithmetic follows IEEE 754 double precision, so results carry about 15 to 17 significant decimal digits and some decimals cannot be represented exactly: 0.1 + 0.2 is not 0.3 in binary floating point. The display is rounded to hide that, not to pretend the stored value is exact.