📊 Percentage Calculator
Calculate percentages in three different ways — fast, accurate, and free.
% of a number
Ratio percentage
Percent change
Result
100
(20% of 500 = 100)
Result
20%
30 is 20% of 150
Result
50% increase
Increase of 25 (50%)
🧮 Understanding Percentages
A percentage is a fraction of 100. It represents a number as a part of a whole. The word "percent" means "per hundred". Percentages are used everywhere: discounts, interest rates, test scores, statistics, and more.
This calculator handles three common scenarios:
- Percentage of a number – e.g., "What is 15% of 200?" → 30
- Ratio percentage – e.g., "45 is what percent of 60?" → 75%
- Percentage change – e.g., "Price increased from 80 to 100" → 25% increase
📐 Percentage Formulas
1. Percentage of a number:
Result = (Percentage × Number) ÷ 100
2. X is what % of Y:
Percentage = (X ÷ Y) × 100%
3. Percentage change:
Change % = ((New - Old) ÷ |Old|) × 100%
📊 Quick Examples Table
| Question | Calculation | Answer |
|---|---|---|
| What is 10% of 250? | (10 × 250) ÷ 100 | 25 |
| 15 is what % of 60? | (15 ÷ 60) × 100 | 25% |
| Increase from 40 to 60 | ((60-40)÷40)×100 | 50% increase |
| Decrease from 80 to 60 | ((60-80)÷80)×100 | 25% decrease |
| What is 25% of 120? | (25 × 120) ÷ 100 | 30 |
| 8 is what % of 32? | (8 ÷ 32) × 100 | 25% |
💡 Real‑life Uses of Percentages
- Shopping: Calculate discounts (e.g., 20% off a $50 item = $10 off).
- Finance: Interest rates, loan APRs, investment returns.
- Statistics: Poll results, pass rates, population growth.
- Cooking: Adjust recipe ingredients proportionally.
❓ Frequently Asked Questions
Multiply the original price by the discount percentage and divide by 100. Subtract that from the original price. Example: 30% off $80 → discount = (30×80)/100 = $24, final price = $80 - $24 = $56.
Percentage change works best with positive numbers. For negative values, the result may be misleading. This calculator assumes positive numbers for clarity.
A percentage point is the arithmetic difference between two percentages. Example: if an interest rate rises from 5% to 7%, that's a 2 percentage point increase, but a 40% relative increase.