Percentage Calculator
Calculate percentages, discounts, tips, and more — instantly.
What is X% of Y?
X is What % of Y?
Percentage Change (Increase/Decrease)
Add or Subtract a Percentage
Tip Calculator
Discount Calculator
Calculation History
No calculations yet. Start calculating!
How to Use the Percentage Calculator
Our percentage calculator makes it easy to solve all types of percentage problems instantly. Simply select the type of calculation you need, enter your numbers, and see the result immediately. All calculations update as you type — no need to click a button.
What This Tool Can Calculate
- What is X% of Y? — Find a percentage of a number. Example: What is 15% of 200? Answer: 30
- X is what % of Y? — Find what percentage one number is of another. Example: 30 is what % of 200? Answer: 15%
- Percentage increase/decrease — Calculate how much a value has changed. Shows whether it's an increase or decrease with color coding.
- Add or subtract a percentage — Add or subtract a percentage from a number. Example: Add 15% to 200 = 230
- Tip calculator — Calculate tips quickly with quick-select buttons for common tip percentages. Includes per-person calculations.
- Discount calculator — See how much you save with a discount and the final price.
Percentage Formulas
Here are the formulas used in this calculator:
- Finding a percentage of a number: (Percentage ÷ 100) × Number
- Finding what percentage one number is of another: (Number ÷ Total) × 100
- Percentage increase/decrease: ((New Value - Original Value) ÷ Original Value) × 100
- Adding a percentage: Number + (Number × Percentage ÷ 100)
- Subtracting a percentage: Number - (Number × Percentage ÷ 100)
Frequently Asked Questions
How do I calculate what percentage one number is of another?
Use the "X is What %" calculator. Enter the first number and the total, and the calculator will show you what percentage the first number represents of the total. For example, if you scored 85 out of 100 on a test, enter 85 and 100 to find that you got 85%.
How can I calculate percentage increase or decrease?
Use the "% Change" calculator. Enter your original value and new value. The calculator will show the percentage change and indicate whether it's an increase (green) or decrease (red). This is useful for comparing price changes, weight loss, or growth metrics.
How do I use the tip calculator?
Enter your bill amount, select or enter a tip percentage, and specify the number of people. The calculator will show the tip amount, total bill, and how much each person should pay if splitting the bill equally.
Can I save my calculation history?
Your calculation history is stored temporarily during your session. The history appears at the bottom of the tool and shows your last 10 calculations. You can clear the history anytime using the "Clear History" button.
How accurate is this calculator?
The calculator is accurate to many decimal places. It performs pure mathematical calculations without rounding errors. For currency (tips, discounts), results are rounded to 2 decimal places for practical use.
Common Percentage Calculations
Here are some real-world examples using this calculator:
- Finding a percentage of a number: "What is 20% off a $50 item?" = $10 savings, $40 final price
- Tip calculation: "What's 18% tip on a $75 bill?" = $13.50 tip
- Percentage increase: "If my salary was $50,000 and now it's $55,000, what's my raise?" = 10% increase
- Test score: "I got 42 out of 50 on a quiz. What's my percentage?" = 84%
- Discount comparison: "Item A is $100 with 25% off. Item B is $85. Which is cheaper?" = Item A is $75, so it's cheaper
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