Do quick maths in your browser. Add, subtract, multiply, divide and work out percentages with this free online calculator — use the buttons or your keyboard.
Tip: you can also type on your keyboard — numbers, +, -, *, /, %, Enter for equals, Backspace to delete and Escape to clear.
1. Click the number buttons (or type on your keyboard). 2. Click an operator: +, -, × or ÷. 3. Enter the second number and click = to see the answer. Use C to clear and the backspace key to delete.
A calculator is the most-searched online tool in the world, and for good reason: everyone needs quick maths every day, from adding up a shopping bill to splitting a restaurant cheque, working out a discount, or checking homework. This free online calculator does the everyday maths in your browser — addition, subtraction, multiplication, division and percentages — with a big, clear keypad that works on a phone, a tablet or a computer. There is nothing to download and no sign-up: just open the page and start typing.
This calculator follows the normal order of operations, so multiplication and division are done before addition and subtraction, exactly like a real calculator and like the maths you learned at school. You can use the on-screen buttons with your mouse or finger, or you can type directly on your keyboard, which is much faster: the number keys, +, -, * and / all work, Enter gives the answer, Backspace deletes the last digit, and Escape clears everything. The % key turns a number into a percentage, so 20% becomes 0.2 in a calculation.
Suppose you buy three items costing 250, 450 and 180, and you want the total. Type 250, press +, type 450, press +, type 180, then press =. The calculator shows 880. Now suppose the shop gives you a 10 percent discount. Type 880, press -, type 10, press % (which turns 10 into 0.1), then press * and type 880? That is one way, but the simpler way is: 880 minus 10 percent of 880. Type 880, press *, type 10, press %, and press =. The answer is 88 — that is the discount. Then 880 minus 88 is 792, which is what you pay. Try both steps in the calculator above and check your answers.
Four friends share a restaurant bill of 3,600, plus a 10 percent tip. First, the tip: 3,600 times 10 percent is 360, so the total with tip is 3,960. Then each person pays 3,960 divided by 4, which is 990. In the calculator: type 3600, press *, type 10, press %, press =, and you get 360. Then type 3600 + 360, press =, and you get 3,960. Then type 3960, press ÷, type 4, press =, and you get 990. Each friend pays 990. The same steps work for any bill: find the tip, add it, and divide by the number of people.
The calculator follows the order of operations, also called BODMAS: brackets first, then orders (powers), then division and multiplication (left to right), then addition and subtraction (left to right). For example, 2 + 3 × 4 is 14, not 20, because the multiplication is done first: 3 × 4 is 12, plus 2 is 14. The calculator also handles brackets, so (2 + 3) × 4 is 20, because the brackets are done first. The % key divides by 100, so 25% is 0.25, and 200 × 25% is 50. Results are rounded to 10 decimal places so that repeating decimals like 1 divided by 3 show as 0.3333333333 instead of a very long number.
Use your keyboard for speed. Typing 250+450 is much faster than clicking each button. Use brackets for mixed sums. When a sum has both + and ×, brackets make your meaning clear. Check big numbers twice. One wrong digit changes the whole answer, so read the display before you press =. Use % for discounts and tips. To find 15 percent of 800, type 800 × 15% and press =. Clear between sums. Press C (or Escape) before a new calculation, so the old numbers do not mix into the new one.
Forgetting the order of operations. 2 + 3 × 4 is 14, not 20, because multiplication comes first. Use brackets when you mean (2 + 3) × 4. Pressing = too early. Pressing = after 250 + shows an error or a partial answer, so finish the whole sum first. Mixing up %. 10% is 0.1, so 500 × 10% is 50, not 5000. Typing two decimal points. A number can only have one decimal point, so 12.5.3 is not valid. Not clearing between sums. If you start typing a new sum without pressing C, the old answer stays in the display and the maths goes wrong.
Pro Tip: To work out a percentage quickly, remember that 10 percent is just the number divided by 10: 10 percent of 3,600 is 360. Then 5 percent is half of that, 180, and 15 percent is 360 + 180, which is 540.
Note: This calculator works entirely in your browser. It does not save your calculations or send them anywhere, so your sums stay private.
Is this online calculator free? Yes, it is completely free, with no sign-up, no download and no limit on how many sums you can do.
Can I use my keyboard with the calculator? Yes. Type numbers and + - * / % directly, press Enter for equals, Backspace to delete a digit, and Escape to clear everything.
Does the calculator follow the order of operations? Yes. Multiplication and division are done before addition and subtraction, just like in school maths. Use brackets to change the order.
How does the % button work? The % key turns a number into a percentage by dividing it by 100. So 25% becomes 0.25, and 200 x 25% gives 50.
Can I calculate a discount with this calculator? Yes. To find the discount, multiply the price by the percent: 880 x 10% = 88. Then subtract: 880 - 88 = 792.
Why does 2 + 3 x 4 give 14 and not 20? Because multiplication is done before addition. 3 x 4 is 12, plus 2 is 14. To get 20, use brackets: (2 + 3) x 4 = 20.
Does the calculator work on my phone? Yes. The keypad buttons are big and touch-friendly, and the display is large enough to read easily on a small screen.
Are my calculations saved anywhere? No. Everything happens in your browser on your own device, and nothing is sent to a server or stored.
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