Online Standard Calculator: Add, Subtract, Multiply, Divide, Percent & Keyboard
A four-function desktop calculator with addition, subtraction, multiplication, division, percentage and sign toggle. Type with the on-screen keypad or your keyboard, repeat the last operation by tapping equals, and copy the result in one click — all computed instantly and privately in your browser.
Standard Calculator Guide
Everyday arithmetic — fast and keyboard-friendly
The standard calculator handles everyday arithmetic: addition, subtraction, multiplication, division, percentages and sign changes. It evaluates left-to-right using simple operator chaining (not algebraic precedence), exactly like a basic pocket calculator. Type with your physical keyboard or tap the on-screen keys; the display shows the current expression at the top and the live result in large digits.
01 Performing a calculation
Tap digits to enter the first number, tap an operator (+, −, ×, ÷), enter the next number, then tap =. You can chain several operations before pressing = — each operator completes the previous operation and shows the running result. Pressing an operator twice in a row does not break the calculation; the latest operator is used.
Use . to enter decimals, ± to flip the sign of the current entry, and % to convert the current entry to a percentage (e.g. 150 × 20 % gives 30). The top line keeps the running expression so you can always see what is being computed; if an operation is invalid (such as division by zero), the display shows Error until you press AC or start a new entry.
- Results are kept until you press AC or start a new calculation
- Pressing = repeatedly re-applies the last operation and operand (e.g. 5 + 2 = = = gives 11)
- All computation runs locally in your browser — nothing is sent anywhere
On-screen keypad
- ACAll Clear — erases the current entry and the running expression.
- ⌫Backspace — deletes the last digit of the current entry.
- %Percent — converts the current number to a percentage factor.
- ÷Division operator.
- ×Multiplication operator.
- −Subtraction operator.
- +Addition operator.
- ±Sign toggle — flips the current number between positive and negative.
- =Equals — completes the calculation. Tap repeatedly to repeat the last operation.
- 0–9Digits for entering numbers.
- .Decimal point for fractional numbers.
Keyboard shortcuts
- 0–9 / .Enter digits and decimals.
- + − * /Add, subtract, multiply and divide.
- Enter / =Compute the result.
- BackspaceDelete the last digit.
- EscClear all (same as AC).
- %Apply the percent operation.
- _Toggle the sign of the current entry.
- For scientific functions (sin, log, powers), use the Scientific Calculator instead.
- The display keeps your last result so you can start a new operation right away.
- If you see Error, press AC to reset and begin a fresh calculation.
A clean, precise online standard calculator for addition, subtraction, multiplication and division, plus percentage, sign toggle and backspace, with full keyboard support (digits, operators, Enter, Backspace, Escape). A large monospaced display automatically groups digits by thousands and shows results instantly. Everything runs locally in your browser — no network, no uploads.
How to use the calculator
Tap the on-screen keys or just type numbers and operators on your keyboard. AC clears everything, ⌫ deletes one digit, % converts the current number to a percentage (divides by 100), ± flips the sign, . enters a decimal point, and = or Enter computes the result. Pressing = repeatedly repeats the last operation; entering a new operator chains the next calculation from the current result.
Keyboard shortcuts
Digits 0–9 enter numbers; +, -, *, / map to add, subtract, multiply and divide (you can also use × and ÷); Enter or = evaluates; Backspace deletes a digit; Escape clears; % takes a percentage; an underscore or a leading minus enters a negative number. Keyboard and mouse behave identically for fast entry.
Precision notes
The calculator uses JavaScript floating-point arithmetic and applies light rounding on display to tame classic binary quirks like 0.1 + 0.2, while keeping plenty of precision. Dividing by zero shows Error — press AC or re-enter to recover. Very large numbers are shown in scientific or compact notation.
Privacy and offline use
All computation happens locally on your device. Nothing is sent to a server and results are never written to history. Once the page loads, the calculator keeps working offline, making it handy for quick everyday arithmetic on any device.
FAQ
QIs this calculator free?
Yes — completely free, no sign-up, no usage limits, no ads. It even works offline once the page has loaded.
QDoes it support keyboard input?
Yes. Digits, + - * /, Enter/=, Backspace, Escape, % and _ (for negatives) all work directly without a mouse.
QAre calculations saved to history?
No. The standard calculator does not write results to history; it resets on refresh, which makes it ideal for quick, throwaway calculations.
QWhat should I do when it shows Error?
Error usually means a division by zero. Press AC to clear and start over. Any other unexpected result from overflow or an invalid expression can be reset the same way.