Percentage calculator
Use one page for three everyday percent questions. The result updates as you enter numbers. Switch modes to change the formula. The calculator does not look up tax tables or loan rates.
Do this next
Open another calculator with the numbers you just entered. The values stay in the link. Nothing is sent to a server.
When to use this calculator
Use the first mode when you already know the percent, and you need the amount, such as 15 percent of 80. Use the second mode when you have two amounts, and you want the percent, such as 12 is what percent of 80. Use percent change when a number moved, such as a price from 80 to 92.
The formulas stay on the page: (percent ÷ 100) × amount; (part ÷ whole) × 100; and ((new − old) ÷ old) × 100. If the old value is zero, percent change cannot be computed, and the calculator reports that next to the field.
This page is for ordinary percents. Sales tax that you want in dollars belongs on the sales tax calculator. A restaurant tip belongs on the tip calculator.
Try these numbers
- What is 15 percent of 80? The result is 12.
- 12 is what percent of 80? The result is 15%.
- If a price moves from 80 to 92, what is the percent change? The result is 15%.
Questions
Why can I not compute percent change from zero?
Percent change divides by the old value. If that value is zero, the division is undefined. Enter a non-zero starting number, or use the other modes.
Does this calculator add sales tax?
No. It only applies the three percent formulas above. To add or remove a tax percent from a dollar amount, use the sales tax calculator.
Where can I read more about percent change?
The guide How percent change is computed here walks through the same formula with a full example.