Percentage Calculator
All-in-one percentage calculator. Find X% of Y, work out what percentage X is of Y, calculate percentage increase or decrease, and add or subtract a percentage from a value.
Find a value
Result
Find the percentage
Result
Percentage change
Percentage Change
Add or subtract a percentage
Result
How to Calculate Percentages
A percentage is a way of expressing a number as a fraction of 100. The word "percent" comes from the Latin per centum, meaning "by the hundred."
X% of Y
To find X percent of Y, use the formula: Result = (X ÷ 100) × Y
Example: 25% of 80 = (25 ÷ 100) × 80 = 20.
What Percentage is X of Y?
To find what percentage X is of Y: Result = (X ÷ Y) × 100
Example: 20 is what % of 80? → (20 ÷ 80) × 100 = 25%.
Percentage Increase / Decrease
Formula: % Change = ((New − Original) ÷ Original) × 100
A positive result means an increase; a negative result means a decrease.
Example: From 80 to 100 → ((100 − 80) ÷ 80) × 100 = +25%.
Adding or Subtracting a Percentage
Add X% to Y: Y × (1 + X/100)
Subtract X% from Y: Y × (1 − X/100)
Example: Add 20% to 150 → 150 × 1.20 = 180.
Frequently Asked Questions
Multiply the number by the percentage and divide by 100. For example, 20% of 150 = (20 ÷ 100) × 150 = 30.
Divide the first number by the second and multiply by 100. For example, 30 is what % of 150? → (30 ÷ 150) × 100 = 20%.
Subtract the original from the new value, divide by the original, and multiply by 100. A positive result is an increase; negative is a decrease.
Multiply the number by (1 + percentage/100). To add 15% to 200: 200 × 1.15 = 230.
Multiply the number by (1 − percentage/100). To subtract 15% from 200: 200 × 0.85 = 170.