Basic calculator
Add, subtract, multiply or divide two numbers. Decimal arithmetic keeps everyday calculations such as 0.1 + 0.2 precise.
Result for the values shown.
Calculations run in your browser.
What to enter
| Input | Meaning and units |
|---|---|
| First number | Enter first number using the definition in the method and example. |
| Operation | Choose the applicable option: Add (+), Subtract (−), Multiply (×), Divide (÷). |
| Second number | Enter second number using the definition in the method and example. |
Understanding your result
Read Result in the units and model stated on this page. The formula a + b · a − b · a × b · a ÷ b defines the relationship; measurement accuracy and model applicability are separate from numerical precision.
Common mistakes
- Using a different mathematical definition or operation than the one stated by this tool.
Check your calculation
- Use the worked example as a known reference case, then change one input at a time and check the direction and units of the response.
Calculation checks, sources and review limits
What is the result of adding, subtracting, multiplying or dividing two numbers?
Choose the operation and enter the two numbers in order. Subtraction and division depend on that order, while addition and multiplication do not.
Common uses
- Check a sum, difference or product.
- Split an amount into equal parts by division.
How it works
Choose an operation and enter two signed values. Addition and multiplication are commutative; subtraction and division use the order shown. Division by zero is undefined. Results use up to 50 significant decimal digits, so repeating quotients are approximations.
Worked example
0.1 + 0.2 = 0.3. Dividing 1 by 3 produces a repeating decimal approximation.