Percentage Calculator
Calculate percentages, percentage change, and reverse percentage.
About This Tool
The Percentage Calculator solves four common percentage problems in one tool: finding what percentage X is of Y, calculating X% of a value, finding the percentage change between two values, and finding the base when a percentage and result are known.
All calculations run instantly in your browser. No data is sent to any server. Results use standard percentage formulas and are rounded for practical use.
How to Use
- Select the calculation mode from the tabs.
- Enter the values for X and Y.
- Click Calculate or press Enter.
- The result appears immediately below.
Use Cases
The Percentage Calculator is used to compute sale prices and discounts, check exam scores as percentages, track revenue growth, calculate conversion rates, and compute investment return percentages.
FAQ
- What is the difference between percentage and percentage points? — Percentage point is the arithmetic difference (5% → 8% = 3pp); percentage change is relative (5% → 8% = 60% increase).
- How do I calculate a discount? — Use "X% of Y = ?" mode. Enter the discount rate as X and the original price as Y to get the discount amount.
- What does a negative result mean? — In "% change" mode, a negative result means a decrease. For example: −10 means a 10% decrease.