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Percentage Calculator
Solve all your percentage problems with our easy-to-use calculator. Calculate percentages, percentage changes, and more.
What is X% of Y?
X is what % of Y?
Percentage Change
X is Y% more/less than?
Percentage Math Made Simple
Honestly, nobody likes doing percentage math in their head. You're at the store, see "30% OFF!" and try to figure out if that $67 sweater is actually a good deal. Your brain pretends to calculate but really you just guess.
That's what this calculator is for. Type in numbers, get answer, done.
💡 Shopping Hack
Check if "50% OFF!" is real—Google the original price. Sometimes that $100 "sale" item was never worth $200.
Quick Percentage Tricks
20% off $80 shoes? Mental math: 10% = $8, so 20% = $16 off. Final price: $64.
Or just use the calculator. Nobody's judging.
⚠️ Common Mistake
Stock goes up 50%, then down 50%. You're back to start, right? Wrong.
$100 → +50% = $150
$150 → -50% = $75 (you lost $25!)
Math Checked by Dr. Lisa Zhang, PhD
Professor of Mathematics, MIT
Lisa makes sure all our formulas are actually correct. (Someone has to.)
Frequently Asked Questions
How do I calculate a percentage?
To find what X% of Y is, multiply Y by (X/100). Example: What's 25% of 200? Answer: 200 × (25/100) = 200 × 0.25 = 50. Or just use our calculator and skip the math.
How do I calculate percentage increase?
Subtract the old value from the new value, divide by the old value, and multiply by 100. Formula: ((New - Old) / Old) × 100. Example: From $100 to $150? ((150-100)/100) × 100 = 50% increase.
What's the difference between percentage and percentile?
Percentage is a fraction of 100 (like scoring 85% on a test). Percentile is your rank compared to others (scoring in the 85th percentile means you beat 85% of test-takers). Totally different things.