How to use
- As you type, the expression appears on top and a live preview of the result below it. Press = to finish the calculation and save it to your history.
- Parentheses work, and a number next to a parenthesis is multiplied, so
2(3+4)gives 14. Missing closing parentheses are added for you. - After a result, pressing an operator continues from that result, while pressing a number starts a new calculation.
Percent (%)
% divides the number before it by 100, so 50% is 0.5 and 80×15% is 15% of 80, which is 12. To work out a 15% tip on a $80 bill, type 80×(1+15%) to get 92. For a 20% discount, 80×(1−20%) gives 64.
Keyboard shortcuts
| Key | Action |
|---|---|
| 0–9 . + - * / % ( ) | Type |
| Enter, = | Calculate |
| Backspace | Delete last character |
| Esc, Delete | Clear all |
FAQ
Does 0.1 + 0.2 give exactly 0.3?
Yes. Computers introduce tiny rounding errors in decimal math (such as 0.30000000000000004), so results are rounded to 12 significant digits before they're shown.
Where is my history saved?
Only in this browser. It is never sent to a server, and you can clear it any time with the Clear button.