Online Calculator
A clear, everyday calculator for adding, subtracting, multiplying, dividing and working out percentages. It runs in your browser and keeps nothing.
Keyboard: digits, + - * /, Enter or =, Backspace, Esc to clear, . or , for the decimal point.
History (last 20)
No calculations yet. Tap a past result to use it again.
How to Use the Calculator
This is a standard four-function calculator that behaves like a desk or phone calculator. Type with the keys on the screen or with your keyboard.
- Enter a number: Tap the digits or type them. Use the
.key (or.or,on your keyboard) for a decimal point, and+/-to change the sign. - Choose an operation: Tap
+,-,xor/. Operations run one after another as you type, so2 + 3 x 4 =gives20. - Press equals: Tap
=to see the result. Press=again to repeat the last operation with the same number. - Use memory and history: Use
M+,M-,MRandMCto keep a running total. Tap an item in the history list to bring its result back.
Key Features
- Exact decimals: Everyday decimal sums come out right:
0.1 + 0.2shows0.3and1.1 x 3shows3.3. - Desk-calculator percent:
200 + 10 %gives220and50 x 10 %gives5, the way a physical calculator does it. - Memory keys:
MC,MR,M+andM-with an indicator that shows when the memory holds a number. - History of 20 calculations: Tap a past result to use it again, copy the current result with one button, or clear the list.
- Keyboard and touch friendly: Large keys, full keyboard support, and a layout that fits a 375 px wide phone screen. Dark mode is supported.
- Private: All maths happens in your browser. Nothing you type is sent anywhere, and the history disappears when you close the page.
What This Tool Can and Cannot Do
This is a standard four-function calculator with percent, square root, reciprocal and memory. It does not know the order of operations: it runs each operation as soon as you press the next one, like most desk calculators. For brackets, powers, trigonometry and logarithms, use the Scientific Calculator page.
Results are shown with about 12 significant digits and very large or very small numbers switch to exponent form, for example 1.2345e+21. Dividing by zero or taking the square root of a negative number shows a short message instead of a number.
Frequently Asked Questions
Why does 2 + 3 x 4 give 20 and not 14?
This calculator runs every operation as soon as you press the next operator, like an ordinary desk calculator. So it works out 2 + 3 = 5 first and then 5 x 4 = 20. To follow the school rule where multiplication comes first, use the Scientific Calculator, which understands order of operations.
How does the percent key work?
After + or - it takes a percentage of the first number: 200 + 10 % is 220 and 200 - 10 % is 180. After x it multiplies and divides by 100: 50 x 10 % is 5. On its own it divides the number by 100.
What do the memory keys do?
M+ adds the number on the display to memory and M- subtracts it. MR brings the memory back onto the display and MC empties it. An M appears at the top of the screen while memory holds a value. Memory is cleared when you close the page.
Why does 0.1 + 0.2 show 0.3 here?
Computers store many decimals as binary approximations, which is why some tools show results like 0.30000000000000004. This calculator adds and multiplies decimals exactly as written and only rounds the display to about 12 significant digits.
What happens if I divide by zero?
The display shows Cannot divide by zero. Press C or CE, or start typing a new number, to carry on.
Is anything saved or uploaded?
No. Calculations happen in your browser, nothing is sent to a server, and the history list lives only in the page until you close or reload it.