Percentage Calculator

Three percentage calculators in one — find amount, find percent, or find total

%

What is X% of Y?

Result
Value
Remaining
Decimal
Double %

Percentage Formulas Explained

Find Amount: Result = (X% ÷ 100) × Y
Example: 15% of 200 = (15 ÷ 100) × 200 = 30
Find Percent: Result = (X ÷ Y) × 100
Example: 30 is what % of 200 = (30 ÷ 200) × 100 = 15%
Find Total: Result = X ÷ (Y% ÷ 100)
Example: 30 is 15% of what = 30 ÷ 0.15 = 200
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Mental math shortcut: To find 10% of any number, just move the decimal left one place. $350 → 10% = $35. Then multiply: 20% = $70, 5% = $17.50, 15% = $52.50.

Common Percentage Quick Reference

CalculationOn $50On $100On $200On $1,000
5%$2.50$5$10$50
10%$5$10$20$100
15%$7.50$15$30$150
20%$10$20$40$200
25%$12.50$25$50$250
30%$15$30$60$300
40%$20$40$80$400
50%$25$50$100$500
75%$37.50$75$150$750

Everyday Percentage Examples

15% tip on $60 dinner$9.00
20% tip on $85 restaurant bill$17.00
8.5% sales tax on $120 purchase$10.20
30% off a $79.99 item$24.00 savings
5% annual raise on $55,000 salary$2,750 more/year
401k contribution: 6% of $80,000$4,800/year

Frequently Asked Questions

What is 15% of 200?

15% of 200 = (15 ÷ 100) × 200 = 30. Quick method: 10% of 200 = 20, 5% of 200 = 10, so 15% = 20 + 10 = 30.

30 is what percent of 200?

(30 ÷ 200) × 100 = 15%. Use the "Find Percent" mode above — enter 30 as X and 200 as Y.

What is 20% of $150?

(20 ÷ 100) × 150 = $30. Commonly used for tips, discounts, and tax calculations.

How do I calculate a percentage tip?

Multiply the bill by the tip percentage divided by 100. For a 20% tip on $75: 0.20 × $75 = $15. For 15%: 0.15 × $75 = $11.25.

How do I calculate sales tax?

Multiply the price by the tax rate divided by 100. For 8% tax on $50: 0.08 × $50 = $4 tax → total = $54.

What does "percent" mean?

"Percent" means "per hundred." 25% means 25 out of every 100, or 0.25 as a decimal. To convert a decimal to a percent, multiply by 100. To convert a percent to a decimal, divide by 100.

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