Free online percentage calculator. Calculate what percent of a number is, find what percentage one number is of another, calculate percentage increase or decrease, find percentage difference, and add or remove a percentage from any number — all in one free tool. Results appear instantly as you type.
How to Use This Percentage Calculator
This tool has five different types of percentage calculations. Simply click the tab for the type of calculation you need, enter your numbers and the answer appears instantly. You do not need to press any button — the result updates as you type.
Type 1 — What Is X Percent of Y
Use this when you want to find a percentage of a number.
How to use it: Enter the percentage in the first box and the number in the second box. The result appears instantly.
Examples of when to use this: You want to know what 20 percent of 500 is to calculate a discount. You want to know what 15 percent of a restaurant bill is to calculate a tip. You want to know what 8.5 percent of your salary is for tax. You want to know what 30 percent off a product price is during a sale.
Example: What is 25 percent of 200? Answer is 50.
Type 2 — X Is What Percent of Y
Use this when you want to find out what percentage one number represents of another.
How to use it: Enter the smaller number in the first box (Value X) and the total in the second box (Total Y). The result shows what percentage X is of Y.
Examples of when to use this: You scored 45 out of 60 in a test and want to know your percentage score. Your company made 80,000 in profit out of 400,000 in revenue and you want the profit percentage. You ate 3 slices out of 8 and want to know what percentage you ate.
Example: 45 out of 180 equals 25 percent.
Type 3 — Percentage Increase or Decrease
Use this when a value has changed and you want to know by how much as a percentage.
How to use it: Enter the original value in the first box and the new value in the second box. The tool automatically shows whether it is an increase or a decrease and by how much.
Examples of when to use this: Your rent went from 800 to 950 and you want to know the percentage increase. Your website traffic dropped from 10,000 to 7,500 and you want to know the percentage decrease. A stock price rose from 120 to 145 and you want to know the percentage gain. Your salary increased from 30,000 to 34,500 and you want to know the raise percentage.
Example: From 100 to 135 is a 35 percent increase. From 200 to 160 is a 20 percent decrease.
Type 4 — Percentage Difference
Use this when you want to compare two values and neither one is the original or reference point.
How to use it: Enter both values and the tool shows the percentage difference between them based on their average.
Examples of when to use this: You are comparing the price of the same product at two different stores. You are comparing two survey results or two test scores from different groups. You want to compare two measurements without saying one is the original.
Example: The percentage difference between 80 and 120 is 40 percent.
Note: This is different from percentage change. Percentage change requires one value to be the original starting point. Percentage difference treats both values equally.
Type 5 — Add or Remove a Percentage
Use this when you want to add a percentage to a number or subtract a percentage from a number.
How to use it: Enter the number in the first box and the percentage in the second box. Then click Add Percent or Remove Percent depending on what you need.
Examples of when to use this: A product costs 400 and there is 18 percent GST to add — click Add to find the total price. A product is 30 percent off its original price of 250 — click Remove to find the sale price. You want to add a 10 percent service charge to a bill. You want to find the price of something after a 15 percent discount.
Example: 500 plus 20 percent equals 600. 500 minus 20 percent equals 400.
Common Percentage Examples
10 percent of 100 equals 10. 25 percent of 200 equals 50. 50 percent of 80 equals 40. A 20 percent discount on a 50 dollar item saves 10 dollars. A 15 percent tip on a 60 dollar bill is 9 dollars. An increase from 80 to 100 is a 25 percent increase. A decrease from 100 to 75 is a 25 percent decrease.
Frequently Asked Questions
How do I calculate a percentage of a number? Divide the percentage by 100 and multiply by the number. For example 15 percent of 300 equals 15 divided by 100 multiplied by 300 which equals 45. Use Type 1 above to calculate this instantly.
How do I calculate a discount? Use Type 5 above. Enter the original price, enter the discount percentage and click Remove Percent. The result shows the discounted price.
How do I calculate percentage increase? Use Type 3 above. Enter the original value and the new value. The tool automatically calculates the percentage increase or decrease.
What is the difference between percentage change and percentage difference? Percentage change measures how much a value has changed from a specific starting point. Percentage difference compares two values equally without either being the original. Use Type 3 for percentage change and Type 4 for percentage difference.
How do I add tax to a price? Use Type 5 above. Enter the price, enter the tax percentage and click Add Percent. The result shows the total price including tax.
Is this percentage calculator free? Completely free. No sign up, no login, no limits.
Related Tools on AllTheTools.com
BMI Calculator — thatsthetool.com/bmi-calculator Age Calculator — thatsthetool.com/age-calculator Gas Cost Calculator — thatsthetool.com/gas-cost-calculator Word Counter — thatsthetool.com/word-counter Date Difference Calculator — thatsthetool.com/date-difference-calculator
Last updated: March 2026 · Free tool by AllTheTools.com