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Use the buttons or keyboard to calculate.
Recent calculationsShort in-browser history for this calculator session.
No completed calculations yet.
Keyboard shortcuts: numbers, decimal point, +, -, *, /, %, Enter or =, Escape and Backspace.
How this basic calculator works
The calculator uses controlled arithmetic logic for addition, subtraction, multiplication and division. It does not run arbitrary code, and it shows a clear warning when a calculation cannot produce a usable result.
Keyboard shortcuts
You can use number keys, decimal point, +, -, *, /, %, Enter or =, Escape and Backspace. Keyboard input is treated the same as pressing the calculator buttons.
Percentage behaviour
A standalone percentage is converted to a decimal. With addition or subtraction, the percentage is based on the stored value, so 200 + 10% becomes 220. With multiplication or division, the percentage acts as a decimal, so 200 × 10% becomes 20.
What this calculator does not include
This is not a scientific calculator. It does not include trigonometry, logarithms, graphing, unit conversion, currency conversion or spreadsheet-style formulas.
Key terms and assumptionsShort notes about percentage behaviour, rounding, divide-by-zero handling and the limits of this basic calculator.
- Percentage button
- A standalone percentage is converted to a decimal. With addition or subtraction, the percentage is based on the stored value, so 200 + 10% becomes 220.
- Rounding
- Results may be rounded for display to keep everyday decimal calculations readable.
- Divide by zero
- Division by zero is not a usable calculator result, so the calculator shows a clear warning instead.
- Basic arithmetic only
- This calculator keeps things focused on everyday arithmetic and percentages. It does not include scientific functions.
- Browser-side calculation
- Calculations run in the browser and do not require an account.
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FAQs
How do I use this calculator?
Enter numbers with the buttons or keyboard, choose an operation, then press equals to see the result.
Can I use my keyboard?
Yes. Number keys, decimal point, +, -, *, /, Enter, =, Escape and Backspace work with the calculator.
Does this calculator support percentages?
Yes. The percentage button supports everyday percentage calculations with simple documented behaviour.
Does this calculator store my calculations?
No. Calculations happen in the browser, and the short history is only for the current calculator session.
Why did I get a divide-by-zero warning?
Dividing by zero does not produce a usable calculator result, so the calculator shows a clear warning instead.
Is this a scientific calculator?
No. This is a basic calculator for everyday arithmetic, not scientific functions.
Can I copy the result?
Yes. Use Copy result to copy the current result if the browser allows clipboard access.
Why does a decimal result sometimes look rounded?
The calculator may round display output to avoid long floating-point strings that are not useful for everyday arithmetic.