How to Calculate Percentages
Work out a percentage of a number, what percent one number is of another, and percentage increase or decrease.
Kinsutools
Percentage Calculator — free, no sign-up
Drag & drop · Instant download
The Three Common Percentage Questions
Most percentage problems fall into three types, and the Percentage Calculator handles all of them:
- What is X% of Y? — e.g. 20% of 150 = 30. Useful for discounts, tips and tax.
- X is what percent of Y? — e.g. 30 is 20% of 150. Useful for scores and shares.
- Percentage change from X to Y — the increase or decrease between two values, useful for growth and price changes.
How to Calculate a Percentage
Step 1: Open the Percentage Calculator Go to the Kinsutools Percentage Calculator.
Step 2: Pick the calculation type Choose which of the three questions you're answering.
Step 3: Enter your numbers Type the two values and read the answer instantly.
Quick Manual Formulas
- X% of Y = (X / 100) x Y
- X is what % of Y = (X / Y) x 100
- Percentage change = ((New - Old) / Old) x 100
Everyday Uses
Discounts, sales tax, tips, exam grades, interest, and comparing before-and-after figures all come down to percentages.
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