Calculator

Online scientific calculator

This free online calculator handles both basic arithmetic and scientific functions. It supports addition, subtraction, multiplication, division, as well as trigonometric functions (sine, cosine, tangent in degrees), square roots, powers, logarithms (base 10 and natural), and mathematical constants like pi and e.

All calculations run entirely in your browser with no data sent to any server. The calculator maintains a history of your computations so you can review and reuse previous results. It responds to keyboard input for fast, efficient calculation.

Keyboard shortcuts

• 0–9 and decimal point (.): Enter numbers directly from your keyboard.
• + - * /: Basic arithmetic operators.
• Enter or = : Evaluate the current expression.
• Backspace: Delete the last entered digit or operator.
• Escape: Clear the current calculation and start fresh.

Scientific functions explained

Trigonometric functions (sin, cos, tan) compute ratios of right triangle sides. This calculator uses degrees, not radians. The inverse functions (typically available as second-function keys) return the angle from a ratio. Logarithm base 10 (log) finds the power of 10 that produces a number, while natural logarithm (ln) uses base e (approximately 2.71828).

The square root function finds the number that, when multiplied by itself, produces the input. The power function (x squared or x to the y) raises a number to an exponent. The reciprocal function (1/x) divides 1 by the input, useful for parallel resistance calculations and other reciprocal relationships.

Calculation tips

For complex expressions, work in stages — calculate inner expressions first, note the result, then use it in the outer expression. Remember the order of operations (PEMDAS/BODMAS): parentheses first, then exponents, then multiplication and division left-to-right, and finally addition and subtraction left-to-right.

Frequently asked questions

Why does the calculator show tiny rounding errors?

Digital computers represent decimal numbers in binary floating-point format, which cannot express all decimal fractions exactly. For example, 0.1 + 0.2 might show as 0.30000000000000004 instead of 0.3. This is a fundamental limitation of IEEE 754 floating-point arithmetic, not a bug in the calculator.

Is my calculation data private?

Yes. All calculations happen locally in your browser using JavaScript. No data is transmitted to any server, and your calculation history is stored only in your browser's memory for the current session.