How to use the basic calculator
- Tap the number and operator keys, or type on your keyboard.
- The whole calculation stays on screen, and the answer appears underneath as you go.
- Press = (or Enter) to finish. The result goes onto the tape, and pressing an operator next carries on from it.
- Use ⌫ to delete the last character and AC to start again.
- M+ adds the current result to memory, M− subtracts it, MR brings it back and MC clears it.
How the calculator works things out
The calculator reads the whole line and applies the standard order of operations, like a scientific calculator or a spreadsheet. Some pocket calculators instead work out each step the moment you press the next operator, so they give a different answer for mixed sums. Brackets can be typed from the keyboard when you need to force an order. The percent key follows the shop-counter convention: after + or −, it takes that percentage of the number before it, which makes adding tax or taking off a discount a single step.
Worked example
The calculator opens at 0. Type 12 + 7 × 3:
- Multiplication comes first: 7 × 3 = 21
- Then the addition: 12 + 21 = 33
A calculator that worked strictly left to right would show (12 + 7) × 3 = 57. If that's what you want, type the brackets.
Adding 15% to 200 is 200 + 15%: 15% of 200 is 30, so the answer is 230. Splitting a $1,250 bill eight ways is 1250 ÷ 8 = 156.25. Dividing by zero shows a dash and the message "You can't divide by zero."
Everyday percent sums
| You want | Type | Answer |
|---|---|---|
| Add 8% sales tax to $45 | 45 + 8% | 48.6 |
| Take 25% off $80 | 80 − 25% | 60 |
| 20% tip on $64 | 64 × 20% | 12.8 |
| 15 as a share of 60 | 15 ÷ 60 × 100 | 25 |
| Price before 20% was added, if it's now $96 | 96 ÷ 120% | 80 |
For more percentage questions, such as percentage change, use the percentage calculator.
Keyboard shortcuts
| Key | Does |
|---|---|
| 0–9 and . | Numbers |
| + − * / | Add, subtract, multiply, divide |
| % | Percent |
| ( ) | Brackets |
| Enter or = | Equals |
| Backspace | Delete the last character |
| Esc | Clear everything |
Frequently asked questions
Why does 2 + 3 × 4 give 14 and not 20?
Because multiplication is done before addition, as in any math class: 3 × 4 = 12, then 2 + 12 = 14. Older pocket calculators that work step by step would show 20. Use brackets, (2 + 3) × 4, when you want the addition first.
How does the ± key work?
It changes the sign of the number you are typing, so 5 becomes −5 and back again. After a result, it flips the sign of that result. A minus sign can also go after × or ÷, as in 6 × −2.
What is the tape?
The tape is a list of the calculations you finished with =, newest first. Tap one to bring it back onto the screen and edit it. It isn't saved, so it clears when you leave the page.
When should I use the scientific calculator instead?
Use the scientific calculator for powers, square roots, logarithms, trigonometry, factorials or scientific notation. This basic calculator keeps to the four operations, percent and memory, so its keypad stays large and easy to tap on a phone.
Related calculators
- Scientific Calculator — Free online scientific calculator with trig in degrees or radians, logs, powers, roots, factorials, memory and history.
- Percentage Calculator — Percent of a number, what percent one number is of another, percentage change and difference.
- Fraction Calculator — Add, subtract, multiply and divide fractions and mixed numbers, simplify fractions and turn decimals into fractions.
- Tip Calculator — Work out the tip and total on a bill, split it between several people, and round each share up if you like.
Results are calculated in your browser. Double-check anything important before you rely on it. See our disclaimer.