Question 1

How do I calculate what X% of Y is?

Accepted Answer

To find X% of Y, multiply Y by X and divide by 100. For example, 15% of 200 = 200 × 15 ÷ 100 = 30. This calculator handles this automatically - just select "What is X% of Y?" and enter your values.

Question 2

How do I find what percent one number is of another?

Accepted Answer

To find what percent X is of Y, divide X by Y and multiply by 100. For example, to find what percent 25 is of 200: (25 ÷ 200) × 100 = 12.5%. Select "X is what percent of Y?" mode in the calculator.

Question 3

What is the difference between percentage change and percentage difference?

Accepted Answer

Percentage change measures the change from an original value to a new value (e.g., price went up 20%). Percentage difference measures how two values differ relative to their average - useful when neither value is the "original" (e.g., comparing two products).

Question 4

How do I calculate percentage increase or decrease?

Accepted Answer

Percentage change = ((New Value - Original Value) / Original Value) × 100. If the result is positive, it's an increase; if negative, it's a decrease. For example, from 80 to 100: ((100-80)/80) × 100 = 25% increase.

Question 5

Can I calculate reverse percentage (find original price)?

Accepted Answer

Yes! If you know a sale price is 20% off, the original was: Sale Price ÷ 0.80. For example, if something costs $80 after 20% off, original = $80 ÷ 0.80 = $100. Use the percentage change mode with the discounted price as the new value.

Percentage Calculator

Percentage Calculator