A calculator for everyday arithmetic
Add, subtract, multiply and divide without installing an app. The calculator also provides percentages, square roots, sign changes, memory and a history of calculations.
This is a standard immediate-execution calculator: operations run as you enter them. For example, 2 + 3 × 4 gives 20 because the addition is completed before multiplication. It is not a scientific expression parser with operator precedence.
How to calculate a percentage
Enter a starting amount, an operation and a percentage, then use %. For example, 200 + 10% adds 10% of 200, giving 220 when you press equals. With multiplication, the percentage is a fraction: 200 × 10% gives 20.
Use percentages for quick discounts and mark-ups. Check the result against the terms of a financial offer before relying on it.
Memory and history
MC clears memory, MR recalls it, M+ adds to it and M− subtracts from it. Calculation history lets you review previous results and reuse them. Use Clear in the history panel to remove entries.
Memory and history belong to the current calculator session. Reloading or leaving the page resets them; they are not stored in an account.
Keyboard controls
Use number keys, +, −, * and / to calculate. Press Enter or = for a result, Backspace to remove the last digit, and Escape to clear. Both the comma and full stop keys can enter a decimal separator.
On a phone, use the touch keypad. The layout adapts to a smaller screen while keeping the controls readable.
Rounding and errors
Results are rounded to reduce ordinary floating-point noise. Very large or very small values may use scientific notation. This calculator is intended for everyday estimates, not arbitrary-precision accounting.
Division by zero and the square root of a negative number show Error. Clear the entry or start typing a new number to continue.
Is this calculator free?
Yes. It works in the browser without registration. Your calculations do not need to be submitted to a calculation server. JavaScript must be enabled.