What is X% of Y?
The classic percentage calculation. Enter a percentage and a number to instantly see the result.
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How this works
Result = Value × (Percentage ÷ 100)To find X% of Y, divide the percentage by 100 to convert it to a decimal, then multiply by the value. For example, 25% ÷ 100 = 0.25, and 0.25 × 200 = 50.
Examples
Sales tax on a purchase
You buy something for $45 in a 7% sales-tax jurisdiction. Tax = 45 × 0.07 = $3.15. Total with tax = $48.15. Knowing how to compute "X% of Y" is the most common real-world percentage calculation.
Commission on a sale
A salesperson earns 8% commission on a $12,500 sale. Commission = 12,500 × 0.08 = $1,000. Straightforward multiplication once the percentage is converted to decimal form.
Down payment on a home
A 20% down payment on a $450,000 house is 450,000 × 0.20 = $90,000. Knowing the down payment lets you compute the loan principal: $450,000 − $90,000 = $360,000.
Nutrition label: % daily value
A food label says 15% of your daily sodium on a 2,300 mg daily value. 15% of 2,300 = 2,300 × 0.15 = 345 mg. One serving contains 345 mg of sodium.
Common questions
Use the 10% trick: move the decimal one place to the left to get 10%, then scale up or down. For 30% of $80: 10% is $8, so 30% is $24. For 5% of $60: 10% is $6, so 5% is $3. For 15%, find 10% and add half of it.
The word comes from the Latin "per centum," meaning "by the hundred." A percentage is a fraction with a denominator of 100. Saying "30%" is the same as saying "30 out of 100" or the fraction 30/100 (which simplifies to 3/10).
Yes. 100% of a number is the number itself, and 200% is twice the number. If a startup grew from 50 users to 200 users, that is a 300% growth rate. Percentages above 100 are common when measuring growth, markups, or multipliers.
If an interest rate goes from 5% to 7%, that is a 2 percentage point increase. But it is a 40% increase in the rate itself (2 ÷ 5 = 40%). News articles often confuse these. "Rose by 2%" and "rose by 2 percentage points" are very different — especially in discussions of inflation, unemployment, or central bank rates.
This calculator gives you the amount when you know the percentage and the total (what is 25% of 200?). The "X is what percent of Y" calculator does the reverse — it gives you the percentage when you know two amounts (25 is what percent of 80?). Use whichever matches what you know and what you need to find out.
No. Everything is computed in your browser. Inputs are never sent to a server. The calculation history is local to your browser and can be cleared any time.