History
This online calculator works like a desk calculator you can also type into: the result appears as you enter the sum, the percent key behaves like the one on a pocket calculator, and every calculation lands in a history you can copy or reuse. It respects the order of operations and handles parentheses, powers and scientific functions.
How to use
- Type with the keypad or your keyboard. The result appears as you type.
- Press = or Enter to finish. The result stays on screen, so you can keep calculating with it.
- Tap f(x) for sin, cos, tan, logs, powers, roots and factorials; DEG switches between degrees and radians.
- Tap a history row to copy its result; tap it again to insert the result into your calculation.
- Percent works like on a pocket calculator: 200 + 10% = 220, 200 − 10% = 180, 50 × 10% = 5.
- Multiplication can be implied: 2π, 3(4+5) and (1+2)(3+4) all work. Missing closing parentheses are added for you.
- Results are rounded to 12 significant digits, so 0.1 + 0.2 shows 0.3.
- You can type function names too: sqrt, sin, cos, tan, asin, ln, log, abs, pi, e and Ans (the last result).
Order of operations
Multiplication and division come before addition and subtraction, and parentheses come first, so 2 + 3 × 4 = 14 and (2 + 3) × 4 = 20. Powers bind tighter still: 2 × 3^2 = 18. Multiplication can be implied, so 3(4 + 5) means 3 × 9 = 27, and missing closing parentheses are added at the end.
Results are rounded to 12 significant digits. That hides the tiny binary rounding errors computers make, which is why 0.1 + 0.2 shows 0.3 here rather than 0.30000000000000004.
How the percent key works
Percent follows pocket-calculator rules. After + or −, it means a percent of the first number: 200 + 10% = 220 and 200 − 10% = 180, handy for tax and discounts. After × or ÷, it is just divided by 100: 50 × 10% = 5. On its own, 15% is 0.15.
Keyboard and history
Type with the number row or keypad: Enter or = calculates, Backspace deletes one character, Esc clears. Tap a history row to copy its result, and tap it again to insert it into the current calculation; Ans also stands for the last result.
Frequently asked questions
How does the calculator handle 2 + 3 × 4?
It follows the order of operations and gives 14: multiplication first, then addition. Use parentheses, (2 + 3) × 4, to get 20.
Why does 0.1 + 0.2 show 0.3?
Computers store decimals in binary, which gives 0.30000000000000004. Rounding to 12 significant digits removes that noise, so you see 0.3.
What does 200 + 10% give?
220. As on a pocket calculator, + 10% adds ten percent of the first number. 200 − 10% gives 180.
Can I use my keyboard?
Yes. Digits, + − * /, ^ for powers, % and parentheses all work; Enter calculates, Backspace deletes and Esc clears.
Is there a scientific mode?
Tap f(x) for sin, cos, tan, logarithms, powers, roots and factorials, and switch between degrees and radians with DEG.
Is my history saved?
Only in this browser on this device. Nothing you calculate is sent to a server.