Percentage Calculator
Instantly calculate percentages — find a percent of a number, work out percentage change, or find what percentage one number is of another. No sign-up needed.
Choose a calculation type
What is X% of Y?
e.g. What is 20% of 150?
X is what % of Y?
e.g. 30 is what % of 120?
Percentage Change
e.g. from 80 to 100 = +25%
Increase / Decrease by %
e.g. 200 increased by 15%
Your result will appear here
Choose a type, fill in the values, then hit Calculate.
How Each Formula Works
Quick reference for the four percentage calculation types
Multiply the number by the percentage and divide by 100. E.g. 20% of 150 = (20 ÷ 100) × 150 = 30.
Divide the part by the whole and multiply by 100. E.g. 30 is what % of 120? = (30 ÷ 120) × 100 = 25%.
Positive = increase, negative = decrease. E.g. from 80 to 100 = ((100 − 80) ÷ 80) × 100 = +25%.
Multiply the original by (1 + P/100) to increase, or (1 − P/100) to decrease. E.g. 200 + 15% = 200 × 1.15 = 230.
All calculations run in your browser. No data is sent to any server — everything stays private on your device.
Common Questions
How do I calculate a percentage of a number?
What is percentage change and how is it calculated?
What is the difference between percentage increase and percentage change?
Is my data saved or shared?
localStorage — your inputs disappear the moment you close the tab.