Dr. Vilma is a Harvard educated doctor specializing in obstetrics, gynecology, and infertility and reproductive endrocrinology. When not in active practice, she creates patient educational materials, academic works, and editorials on health advocacy and wellness.
A percentage calculator can simplify your life and save you time in a number of different scenarios. Even if you are a math whiz, an online calculator is a modern tool that can make your life easier. Access and use our simple-to-use widget any time you need to calculate percentages.
How to Use the Widget
The online widget can make calculations for various scenarios in seconds. Whether you are on your computer, tablet, or phone, the built-in math formulas make the calculations accurate and efficient. To use the widget:
Type your numbers in the appropriate boxes
Click "Calculate" to display your answer.
Click "Clear Results" to perform new calculations.
There are many instances where the calculation of a percentage comes in handy, including:
Quick calculations while shopping or dining
Mortgage interest payments
Percent increase or decrease in mortgage or rent payments
Percent growth in business profit
Percent of income spent on bills
Tracking the percentage of household budget spent on groceries
Types of Calculations Available
The following examples illustrate the types of calculations the percentage widget can make. The math formulas are included for your reference.
1. One Number as a Percentage of Another
When you want to to find what percentage one number is of another number, the calculator can easily make this calculation.
The Formula: Percentage = (first number/second number) x 100%
Divide the first number by the second and multiply the result by 100%
Example: You spent $150 this week on food and you have a total food budget of $200. What percentage of your food budget did you spend? What percentage of $200 is $150?
Calculation: ($150/$200) x 100% = 75% of your food budget spent
2. Percentage Amount of a Particular Number
You have a particular number and you want to find a certain percentage amount of that number. This is useful for paying a tip when eating out.
The Formula: Percentage Amount = {(given percentage/100%) x particular number}
Divide the given percentage by 100% and multiply the result by the particular number.
Example: You have just finished dining in a restaurant and you want to know what amount to leave for a tip. Your bill is $100 and you want to leave a 15% tip. What is 15% of $100?
Calculation: (15%/100%) x $100 = $15 tip
3. Total When a Number Equals a Certain Percent of the Total
When you have a number and know the percentage of the total that the number represents, you can calculate the total amount.
The Formula: Total = {(number x 100%)/percentage}
Multiply the number by 100% and divide the result by the percentage to get the total.
Example: The $20 you paid on your phone bill this month represents 10% of the total. What was your total phone bill? Or, $20 is 10% of what total?
Calculation: ($20 x 100%)/10% = $200 total phone bill
4. New Amount from Percentage Discount
You can calculate the new amount for an item based on the percentage of the discount on the original. This math operation is useful when store items go on sale for a certain percentage off.
The Formula: New amount = original amount - {(percent discount/100%) x original amount}
Divide the percent discount by 100%.
Multiply that result by the original amount to get the amount of the discount.
Subtract the discount amount from the original amount to get the new amount.
Example: A dress you are trying to buy is on sale for 20% off and the original price is $100. What is the new sale price of the dress?
Calculation:
20%/100% = 0.2
0.2 x $100 = $20, the discount amount
$100 - $20 = $80, the new sale price of the dress
5. Percentage Change
When a number increases or decreases, calculate the percentage change in the old number.
The Formula: Percentage change (increase or decrease) = {(bigger number - smaller number)/original number} x 100%}
First, get the difference between the old and the new number by subtracting the smaller number from the bigger number. This applies for both increases and decreases.
Divide the answer from above by the original number.
Multiply the new answer by 100% to get the percentage increase or decrease.
Example: Your car insurance increased from $1,000 to $1,200 per year. What is the percentage increase in your insurance?
Calculation:
$1200 - $1000 = $200
$200/$1000 = 0.2
0.2 x 100% = 20% increase in your car insurance
A Very Handy Calculator
An online percentage calculator can be useful in many parts of your life. Although you can do some simple calculations in your head or make use of the formulas provided here, you will definitely find this calculator advantageous, especially for more complex percentage computations.
