Calculator

How To Use The Calculator

Type your numbers with the on-screen keypad or your physical keyboard, then choose an operator: + to add, - to subtract, x to multiply, or / to divide. Press = (or Enter) to see the result. The % key turns the current value into a percentage, +/- flips the sign, Del removes the last digit, and C clears everything back to zero. Because the result stays on screen, you can press another operator straight away and keep calculating from it.

How Order Of Operations Works

A basic calculator follows the same precedence rules you learned in school, known as PEMDAS in the United States and BODMAS in the United Kingdom. Both spell out the same priority: brackets first, then exponents (orders), then multiplication and division, and finally addition and subtraction. The practical consequence is that an expression like 2 + 3 * 4 is not read left to right; the multiplication happens first, giving 14, not 20. When two operators share the same priority, such as a chain of additions and subtractions, they are evaluated from left to right.

Precedence Examples

The table below shows how precedence changes the answer. Each expression is written the way you would type it, with the result the calculator returns once the priority rules are applied.

A basic calculator has no exponent key, so in everyday use the order reduces to: brackets, then multiply and divide, then add and subtract.

Worked Example: Adding Sales Tax

Say an item costs 49.99 and the tax rate is 8 percent. First find the tax: enter 49.99, press multiply, enter 8, then press % to get 4.00. Now add that to the price: the running total of 49.99 + 4.00 gives 53.99. Because each result carries over, you never have to write the intermediate figure down, and decimals are kept at full precision until you read the final number.

Why This Tool Is Useful

Most quick sums do not need a spreadsheet or a phone app. This calculator loads instantly in the browser tab you already have open, which makes it ideal for splitting a bill, checking a receipt total, converting a fraction to a decimal, or working out a percentage discount while you shop. Keyboard support means you can type a long calculation as fast as you can read it, and the on-screen keypad keeps it usable on a phone or tablet.

Accuracy And Privacy

Every calculation runs locally in your browser using its native arithmetic, so nothing you type is uploaded, logged, or stored on any server. The results follow standard precedence and full decimal precision, though like all binary floating-point math a few divisions can produce a long trailing decimal. For important financial, tax, or engineering decisions, treat the output as a fast estimate and confirm the final figure against your source data.