Percentage Calculator

Percentage math,
solved instantly.

The three most common percentage problems, all solved instantly with no algebra required.

📝 What is X% of Y?
30
15% of 200 = 30
📊 X is what % of Y?
15%
30 is 15% of 200
📈 Percentage change
+25%
80 to 100 = +25% increase
🎭 Add or remove %
Add: 120 Remove: 80
Quick percentage formulas
💡
To find 10%: just move the decimal point one place left. 10% of 350 = 35. For 5%, halve that. For 20%, double it. Mental math hack.
📈
Percentage change formula: (New - Old) / Old x 100. If something went from $80 to $100, that is a 25% increase, not 20%.
🎭
Tip shortcut: For an 18% tip, find 10% (move decimal), add half of that (5%), then add another 3%. Total = 10+5+3 = 18%.