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Percentage Calculator
Three quick percentage tools in one — find a percentage of a number, work out what percent one number is of another, or calculate a percentage increase or decrease. Results update as you type.
What is X% of Y?
X is what percent of Y?
Percentage increase / decrease
Calculate any percentage the easy way
Percentages come up everywhere — discounts, tips, taxes, grades, statistics and growth rates. This percentage calculator covers the three questions people ask most, and works them out instantly as you type. Nothing is uploaded; it all runs in your browser.
The formulas behind it
- X% of Y = Y × X ÷ 100. Example: 20% of 150 = 30.
- X is what % of Y = X ÷ Y × 100. Example: 30 is 20% of 150.
- Percentage change = (new − old) ÷ old × 100. Example: 150 → 180 is a 20% increase.
Everyday uses
- Work out a discount: 30% off a $80 item saves $24.
- Add a tip: 15% of a $46 bill is $6.90.
- Check a test score: 42 out of 50 is 84%.
- Measure growth: followers from 1,200 to 1,500 is a 25% increase.
Frequently asked questions
How do I find a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 is 150 × 20 ÷ 100 = 30. Use the first box above to do it instantly.
How do I calculate percentage increase?
Subtract the old value from the new value, divide by the old value, and multiply by 100. The third box does this — a positive result is an increase, a negative one is a decrease.
Is anything I type saved?
No. All calculations happen locally in your browser and nothing is stored or sent anywhere.