Percentage calculator
Find X% of a number, what percentage one number is of another, and the percentage increase or decrease between two numbers.
Runs in your browser. Nothing you enter is uploaded.
What it does
Three everyday percentage questions in one place: a percentage of an amount, one number as a percentage of another, and the percentage by which something went up or down.
How to use it
- Choose the question you want answered.
- Enter X and Y. The question shows which number is which.
- Read the answer, shown with the working.
Worked example
15% of 2,400 is 360. And 360 is 15% of 2,400. If a bill goes from ₹2,400 to ₹2,760, the change is +15%.
How it works
X% of Y = Y × X ÷ 100. X as a percentage of Y = X ÷ Y × 100. Percentage change from X to Y = (Y − X) ÷ X × 100, which is positive for an increase and negative for a decrease. The last two are undefined when the number you divide by is zero.
Questions
Why can’t I get a percentage change from zero?
Percentage change divides by the starting value. Starting from zero there is nothing to compare with, so the result is undefined.
If a price rises 20% and then falls 20%, is it back where it started?
No. 100 rises to 120, and 20% of 120 is 24, so it falls to 96. The two percentages are taken of different amounts.
What is the difference between percent and percentage points?
If a rate moves from 5% to 7%, it has risen by 2 percentage points, which is a 40% increase.