Percentage Calculator
Guide: How Loan Payments Are Calculated (With a Worked Example)
What is X% of Y?
30
X is what percent of Y?
20%
Percentage change from X to Y
+50% increase
Add or subtract a percentage
+15% = 230 · −15% = 170
Nothing you enter or choose here leaves your device. This tool runs in your browser.
How to use
- 1Find the calculator that matches your question.
- 2Type your two numbers into its boxes.
- 3The answer updates instantly as you type.
- 4Use the other calculators for related questions.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 is 150 x 20 / 100 = 30.
How do I calculate percentage change?
Subtract the old value from the new value, divide by the old value, and multiply by 100. Going from 50 to 75 is a 50% increase.
What if the starting value is zero?
Percentage change from zero is undefined, so the calculator shows a dash instead of a number.
How do I add VAT, tax or a discount?
Use "Add or subtract a percentage". Enter the price and the rate to see the price with it added and with it taken off.
Read the guides
Learn how this works and how to get the most from it.
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How Loan Payments Are Calculated (With a Worked Example)
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How to Calculate Hours Worked, Overnight Shifts and Pay
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How to Calculate a Tip, Sales Tax and VAT
Easy ways to work out a tip and split a bill, and how to add or remove sales tax and VAT from a price without the common mistake.
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