Percentage Calculator

Percentage Calculator — 5 Calculations in One

Percentages are everywhere: tips, tax, sales, exam scores, investment returns, body-fat percentage, website conversion rates. This calculator answers the five questions people ask most often about percentages.

The Formulas

• X% of Y: (X / 100) × Y
• X is what % of Y: (X / Y) × 100
• % change from X to Y: ((Y − X) / X) × 100
• Increase X by P%: X × (1 + P/100)
• Decrease X by P%: X × (1 − P/100)

Percentage vs. Percentage Point

Be careful with the distinction. If an interest rate rises from 4% to 5%, that's a 1 percentage point increase — but a 25% percentage increase (5 is 125% of 4). This tool handles both cases cleanly, but knowing the difference will save you from misreading news headlines.

Everyday Examples

• A $80 meal with a 20% tip = $96.
• A $200 jacket marked down by 30% = $140.
• A stock going from $50 to $55 = 10% increase.
• A test score of 42/50 = 84%.