What is a percentage calculator?
A percentage calculator solves the three most common percentage questions: what is X percent of Y, X is what percent of Y, and by what percent did a value change. It saves you from doing the maths by hand.
How to use it
- Choose the type of calculation.
- Enter your two numbers.
- Read the answer, which updates as you type.
Common uses
- Discounts and sale prices
- Exam marks and grades
- Salary or price increases
- Business growth and statistics
Tips
- Percentage change uses the old value as the base.
- A 50 percent increase followed by a 50 percent decrease does not return to the start.
- Round only at the end for the most accurate result.
Related guide: how to calculate percentage with examples.
Frequently asked questions
How do I find 20 percent of 150?
Choose What is X% of Y, enter 20 and 150, and the answer is 30.
What is percentage change?
It is the difference between the new and old value, divided by the old value, times 100.
Can I use decimals?
Yes. Decimal numbers work in every field.