Online Calculator

How the calculator works: operations, order of calculation, and precision

This calculator accepts basic operations (addition, subtraction, multiplication, and division) and useful functions such as square root, power, and exponential. You can build complete expressions and view the result on the display before confirming.

The evaluation follows the order of operations (also known as precedence): parentheses first, then powers/roots, followed by multiplications/divisions, and finally additions/subtractions. When typing in sequence, the calculator respects this priority to avoid unexpected results.

• Precedence: parentheses → powers/roots → multiplication/division → addition/subtraction.
• Decimal points: use “.” as the separator; the calculator converts it internally to a number.
• Rounding: the displayed value may be rounded for readability; calculations use the browser’s native precision.
• Limits: extremely long expressions may be truncated to preserve performance.

Step by step: performing your first calculation

1. Enter the numbers using the keyboard or the on-screen buttons.
2. Choose the desired operation (e.g., “+”, “−”, “×”, “÷”).
3. For square root, power, or exponential, click the corresponding button.
4. Review the display; if needed, clear using “C” and start again.
5. Confirm with “=” and copy the result if you need to reuse it.

Tip: combine operations into a single expression to reduce steps and minimize typing errors.

Practical examples

• Simple discount: for a 15% discount on $200, use 200 * (1 - 0.15) = 170.
• Rule of three: if 8 items cost $120, how much do 5 cost? 120 / 8 * 5 = 75.
• Power: 3 ^ 4 returns 81.
• Root: press √ and enter a number, e.g. √ 81 = 9.

Common errors and how to fix them

• Incomplete expression (unclosed parenthesis or extra operator). Solution: clear with “C” and rewrite the full expression.
• Using a comma as a decimal separator. Solution: replace it with a dot (e.g., 2.5).
• Division by zero. Solution: review the expression and avoid zero denominators.
• Result “NaN” or “Infinity”. Solution: simplify the expression, validate each part, and try again.

Accessibility and shortcuts

The calculator is designed for use with mouse, touch, and screen readers. Whenever possible, describe actions and review the display before confirming.

• Keyboard: numbers (0–9) and operators (+, −, *, /, .) work in the input field.
• Confirmation: use Enter to calculate and Esc to clear the display.
• Screen readers: the display field announces the current value; navigate through buttons logically.
• Touch: buttons have a large area for comfortable use on mobile devices.

FAQ — frequently asked questions

Quick glossary

• Precedence - The order in which operations are evaluated in an expression.
• Rounding - Reducing decimal places to display a number more clearly.
• Floating point - A way computers represent real numbers that can introduce small differences in results.