Basic CalculatorFree online math calculator — instant results, no sign-up
Simple arithmetic on two numbers.
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About the Basic Calculator
The Basic Calculator performs fundamental two-number arithmetic operations: addition, subtraction, multiplication, and division. It provides quick answers for elementary calculations without complex multi-step input configurations.
- A
- The first numerical value (operand), which can be any positive, negative, or decimal number.
- Op
- The arithmetic operation to execute, selected from addition (+), subtraction (−), multiplication (×), or division (÷).
- B
- The second numerical value (operand), which can be any real number (non-zero when dividing).
Formula and method
Result = A + B (addition) | A − B (subtraction) | A × B (multiplication) | A ÷ B (division)
- AFirst operand
- BSecond operand
- ResultOutcome of the chosen arithmetic operation
The tool parses both inputs as numerical values and applies the selected arithmetic operator. The final output is formatted to display up to 10 decimal places of precision.
Worked example
These are the calculator's starting values and the results it actually produces for them.
Inputs
- A12
- Op+
- B4
Results
- Result16
How to use the Basic Calculator
- 1Enter the initial number into input field A.
- 2Select the arithmetic operator (+, −, ×, or ÷) from the dropdown menu.
- 3Enter the second number into input field B.
- 4Read the calculated outcome in the Result field.
Reading your result
The result displays the exact single-operation total, difference, product, or quotient of the two inputs. If dividing by zero, standard floating-point behavior applies (yielding Infinity or an undefined result).
Limitations
The calculator only evaluates two operands at a time and does not support chained expressions, parentheses, or automated order-of-operations (PEMDAS). It also does not compute advanced functions such as powers, roots, or percentages directly.
Common questions
What happens if I divide by zero?+
Dividing any non-zero number by zero produces Infinity, whereas dividing zero by zero produces NaN (not a number), reflecting mathematical undefined values.
How many decimal places does the calculator support?+
The result displays up to 10 decimal places, truncating unnecessary trailing zeros for whole numbers and shorter decimals.
Can I input negative numbers?+
Yes, you can enter negative values into both input A and input B by prefixing the value with a minus sign.
Does the calculator save my information?+
Calculations run in your browser. While signed in, inputs and results are automatically recorded in account history; saving a result creates a separate saved record.
Further reading
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Results are estimates for informational purposes and are not financial, medical or legal advice.