Basic Calculator

Use + - * / ^ ( ) and % for remainder. Multiplication and division are done before addition and subtraction. In "words" mode, type the sum in plain English instead.
Comma or space separated. The chosen operation is applied left to right.
Exact mode reads every decimal you type as a fraction and works in whole-number numerators and denominators. It cannot use pi, e or functions such as sqrt.
Name a value the expression may use, e.g. "l = 12, w = 7" with an expression of 2 * (l + w).
Changes how the answer is written out. It never changes the arithmetic.
Result
33
Basic Arithmetic Calculator
Unrounded result
33
Expression evaluated
12 + 7 * 3
Result with separators
33
Result as a fraction
33
Operation
Expression
Arithmetic used
Binary floating point (IEEE-754 double)
Worked out from ISO 80000-2, Quantities and units — Part 2: Mathematics (operator symbols and precedence) and 3 other sources.

How this is worked out

3 steps
  1. Evaluate 12 + 7 × 3 using standard operator precedence.
  2. 7 × 3 = 21 → 12 + 21
  3. 12 + 21 = 33 → 33
Step-by-step workingtable
7 × 3 = 21 → 12 + 21, 12 + 21 = 33 → 33

Results are general information, not financial, tax, legal, medical or engineering advice.