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Online Calculator

A free online calculator for everyday math: add, subtract, multiply, divide and work out percentages using your keyboard or by tapping the keys on your phone.

FreeNo sign-upInstant resultsUpdated:

Calculator

0

Works with your keyboard too: numbers, + − * /, Enter, Backspace and Esc.

Recent calculations

Your last 5 calculations will show up here. They're cleared when you leave the page.

Follows the order of operations: × and ÷ are done before + and −. A % after + or − applies to the running total (200 + 10% = 220).

Keep analyzing

For estimates only. Double-check the numbers before making important decisions.

How to use it

  • Keyboard: type numbers and use + − * / to operate. Press Enter or = for the result, Backspace to delete a digit and Esc to start over.
  • Mouse or touchscreen: click or tap the keys on the calculator.
  • Chained calculations: after you get a result, press an operator to keep working with it.
  • History: your last 5 calculations stay on screen while the page is open.

What each key does

KeyWhat it does
ACClears everything and starts from zero
⌫Deletes the last digit you typed
%Turns the current number into a percentage
±Switches the number between positive and negative
.Decimal point

Order of operations

The calculator follows standard order of operations: multiplication and division come before addition and subtraction. That means 2 + 3 × 4 equals 14, not 20.

2 + 3 × 4 = 2 + 12 = 14
200 + 10% = 200 + 20 = 220
50 × 10% = 50 × 0.1 = 5

How the % key works

The % key works like the one on a phone calculator. After + or −, it takes that percentage of the running total, so 80 − 25% gives 60. After × or ÷, or on its own, it simply divides the number by 100.

Precision

Results are rounded to 12 significant digits to avoid the usual floating-point glitches, so 0.1 + 0.2 shows 0.3 instead of 0.30000000000000004. For exact answers with fractions, use the fraction calculator.

Example

Dinner for two: 2 entrées at $18.75 plus a $9.50 appetizer. Type 2 × 18.75 + 9.5 and press = to get 47. To add a 20% tip, press + 20 % = and you get 56.4, or $56.40.

  1. 2 × 18.75 = 37.5
  2. 37.5 + 9.5 = 47
  3. 47 + 20% = 47 + 9.4 = 56.4

Common mistakes

  • Expecting 2 + 3 × 4 to equal 20: multiplication is done first, so the answer is 14.
  • Typing a comma as a thousands separator: on the keyboard the comma is read as a decimal point, so type 1500, not 1,500.
  • Expecting % to always divide by 100: after + or − it takes a percentage of the running total (200 + 10% = 220).

Frequently asked questions

How does the percent key work?

After + or −, it calculates that percentage of the total so far (200 + 10% = 220). After × or ÷, or on its own, it divides by 100 (50 × 10% = 5).

Does this calculator follow order of operations?

Yes. Multiplication and division are done before addition and subtraction, so 10 − 4 ÷ 2 equals 8.

What happens if I divide by zero?

You get an error message instead of a result. Press AC or start typing a new number to continue.

Are my calculations saved?

No. The history only exists while the page is open and is never sent to a server.

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