Basic Calculator
Four-function arithmetic on two numbers with a percentage mode and step-by-step breakdown.
Inputs
For add/subtract: B% of A is added or subtracted. For multiply: result = A × (B/100). For divide: result = A ÷ (B/100).
Result
215.0000000000
Step by step
Inputs
= A = 200, B = 15
Apply operation
200 + 15
= 215
How it works
This calculator performs standard four-function arithmetic on two numbers. The optional percent mode follows the convention of physical calculators: for addition and subtraction the second number is treated as a percentage of the first (so 200 + 15% adds 30, not 0.15); for multiplication and division it divides by 100 first.
Formulas
Addition
Result = A + B
- A
- First operand
- B
- Second operand
Percent-of add
Result = A + (B% × A) when percent mode is on
- A
- First operand
- B
- Percent value
Frequently Asked Questions
What does the percent toggle do on addition?
It converts the second number into a percentage of the first before adding. So 200 + 15% means 200 + (15% of 200) = 200 + 30 = 230 — the same as most physical calculators and spreadsheets.
Why does 1 ÷ 3 show many decimal places?
The result is a repeating decimal (0.333…). The calculator shows up to 10 decimal places so you can see the precision. For exact results, use the Fraction Calculator instead.
Can I chain multiple operations?
This calculator is intentionally designed for one operation at a time. For chained expressions, use the Scientific Calculator which supports a full expression parser.