Percentage Calculator

Five percentage questions, one calculator. Pick the one you are asking, type the numbers, and press Display result to see the answer with the working underneath.

What is X% of Y? X is what % of Y? Increase Decrease Difference

Percentage (%)

Of what number

How to Use the Percentage Calculator

Choose the kind of percentage question you are answering.
Type your numbers into the fields.
Read the answer, along with the working that produced it.

What You Can Do

Work out a percentage of a number, such as 15% of 240.
Find a percentage increase or decrease between two values.
Tell percentage change apart from percentage difference, which are not the same measure.
Copy the result rather than retyping it.

Frequently Asked Questions

How do I calculate a percentage of a number?

Divide the percentage by 100 and multiply by the number. For 15% of 240 that is 0.15 × 240, which is 36.

What is the difference between percentage change and percentage difference?

Percentage change measures movement from a starting value, so the order matters. Percentage difference compares two values against their average, so the order does not.

How do I work out a percentage increase?

Subtract the old value from the new one, divide by the old value, then multiply by 100.

Why can a percentage decrease never be more than 100%?

Falling by 100% leaves nothing. Anything beyond that would take the value below zero, which a decrease cannot do.