Percentage Calculator
Calculate a percent of a number, find what percent one number is of another, or measure an increase or decrease. The three widgets below are a quick start. Each formula also has a dedicated page with worked examples, and a matching practice game.
All percentage tools
The homepage widgets cover the three most common questions. Open a dedicated page when you need a different formula, shopping labels, or a worked example.
Core tools
Everyday tools
Learn
The three core formulas
Most percentage questions are one of these three. Open the matching calculator for a worked line, or read the full method on the how-to guide.
Percentage change
((new − original) / original) × 100. 50 to 65 is a 30% increase.
Step-by-step method
Worked examples for all three operations, plus when to use reverse percentage instead.
Everyday percentage tasks
Shopping and bills use the same core math with different labels. Open the tool that matches the words on the receipt.
Discounts
Take a percent off a price, find the discount percent, or recover the original.
Sales tax
Add a tax percent, or work backwards to the pre-tax amount. Enter the rate yourself; there are no location tables.
Quick answers
Use the three widgets on this page for percent of a number, what percent, and increase or decrease. Open the calculators directory when the question uses other words, such as discount, markup, or margin.
Divide the percent by 100 and multiply by the number. 15% of 80 is 12. The first widget and the dedicated percent-of page both do this.
No. Change uses a starting value and can be an increase or a decrease. Difference uses the average of the two numbers and has no direction.
Yes. Three timed games match the widgets on this page: percent of a number, what percent, and percentage change.
Yes. Percentage is a free offline Android calculator for discounts, tax, tips, marks, and practice. No ads, no account, and no internet permission.