Percentage calculator
Three everyday percentage sums in one place, with answers as you type.
What is X% of Y?
100
X is what percent of Y?
75%
Percentage increase / decrease
+25% increase
How to use the percentage calculator
- Pick the calculation you need.
- Enter the two numbers.
- Read the answer — it updates instantly.
When it's useful
- Working out a 15% markup or discount
- Exam marks as a percentage
- How much a price rose or fell
Limits to know
- Percentage change from zero can't be calculated, because you can't divide by zero.
Your privacy
Everything is worked out in your browser. What you type isn't uploaded, saved or shared, and there's no sign-up.
Questions
How do I calculate a percentage increase?
Subtract the old value from the new, divide by the old value and multiply by 100. The third box does it for you.
What is 20% of 500?
100 — multiply 500 by 20 and divide by 100.