Percentage Calculator
Percentage calculator: what percent is X of Y, what is P% of Y, and Y if X is P% of it, in one tool.
p = partwhole · 100 %
How to use this calculator
- Choose the quantity you want under “Solve for”.
- Type the known values and pick their units: any combination works.
- The result updates as you type. Open “Show the steps” to see the substitution.
A percentage expresses a part as a fraction of a whole multiplied by 100: p = part/whole × 100 %.
Choose what to solve for: the percentage, the part (P% of a number) or the whole (the number of which X is P%).
Formula
p = partwhole · 100 %
| Symbol | Quantity | Units |
|---|---|---|
| W | Part | — |
| G | Whole | — |
| p | Percentage | %, × |
Worked example
Given: W = 30 · G = 120
p = WG
Result: p = 25 %
Frequently asked questions
What is 15 % of 80?
part = 0.15 × 80 = 12.
How do I calculate a percentage increase?
Divide the difference by the original value: (new − old)/old × 100 %.