Percentage Calculator
Choose a calculation type, enter your values, and click Calculate.
If you have ever wondered how to get percentage in calculator, you are not alone. Percentage questions show up everywhere: discounts, exam scores, tips, taxes, salary raises, business reports, and even fitness tracking. The good news is that percentage math is simple once you know the right pattern.
Quick formula you should remember
Most percentage problems come down to one of these three formulas:
- X% of Y = (X / 100) × Y
- X is what % of Y = (X / Y) × 100
- % change = ((New − Old) / Old) × 100
If you remember these, you can solve almost every basic percentage question on any calculator.
How to get percentage on a basic calculator
1) Find a percentage of a number (example: 20% of 150)
Method using formula:
- Type 20 ÷ 100 and press equals (you get 0.2)
- Multiply by 150
- Result: 30
So, 20% of 150 is 30.
2) Find what percent one number is of another (example: 45 is what % of 60?)
- Type 45 ÷ 60 and press equals
- Multiply by 100
- Result: 75%
3) Find percent increase or decrease (example: from 80 to 100)
- Subtract: 100 − 80 = 20
- Divide by original value: 20 ÷ 80 = 0.25
- Multiply by 100: 25%
That means the value increased by 25%.
How to use the % key (if your calculator has one)
Many physical and phone calculators have a percent key. The behavior can vary slightly by brand, but usually these shortcuts work:
- Find discount: For a $200 item with 15% discount, type 200 × 15 % to get 30, then subtract from 200.
- Add tax: For 8% tax on $50, type 50 × 8 % to get 4, then add to 50.
If your calculator gives unexpected results, use the formulas above directly. They always work.
Real-life percentage examples
Discount in shopping
A jacket costs $120 with a 25% discount.
- Discount amount = 25% of 120 = 30
- Final price = 120 − 30 = $90
Exam score
You got 42 marks out of 50.
- Percentage = (42 ÷ 50) × 100 = 84%
Salary raise
Your salary changed from $3,000 to $3,300.
- Change = 300
- Percentage increase = (300 ÷ 3000) × 100 = 10%
Common mistakes to avoid
- Forgetting to divide by 100 when finding X% of a number.
- Using new value instead of old value in percent change calculations.
- Mixing up part and whole in “what percent” problems.
- Rounding too early, which can cause small errors in final answers.
FAQ: how to get percentage in calculator
Can I calculate percentages without a % button?
Yes. Use the formulas shown above. They work on every calculator, including simple ones.
What is the fastest way to find 10%?
Move the decimal one place left. Example: 10% of 460 = 46.
How do I calculate GST or sales tax?
Multiply price by tax rate/100 to get tax amount, then add it to the original price.
Final takeaway
To master percentages on a calculator, focus on three skills: finding a percent of a number, finding what percent one number is of another, and calculating percent change. Use the calculator above for instant answers, and keep the formulas handy for quick manual checks.