How to calculate percentages

Find the percentage of a number

You may wish to find how much discount you are getting on a product you are buying or work out how much tax you should pay. This is where knowing the percentage of a number is very useful.

As an example we will calculate 15% of 200.

Step 1 - Divide

Divide the percentage by 100 (15 / 100 = 0.15). This gives us a decimal number (0.15)

Step 2 - Multiply

Multiply the number by the decimal we calculated in step 1 (200 * 0.15 = 30)

Result

And that's all! The answer in our example is 30%.

Use our percent of a number calculator to work this out for you.

Find the percentage one number is of another

This calculation is useful to find what percentage one amount is of a larger amount. You will see this in use in many places such as food packaging where we can see what a particular ingredient is of the overall amount.

As an example we will calculate what 15 is of 60.

Step 1 - Divide

Divide the first number by the number it is a percentage of. (15 / 60 = 0.25)

This gives us a number (0.25)

Step 2 - Multiply

Multiply the number we calculated in step 1 by 100. (0.25 * 100 = 25)

Result

The answer for our example is 25%.

Use our What percentage one number is of another calculator to work this out for you.

Find the percentage increase from one number to another

Lots of things go up in number from what you earn, to prices and even scores in a game. This calculation allows you to measure how much the increase is using percentages.

As an example we will calculate what the percent increase from 40 to 70 is.

Step 1 - Subtract

Subtract the original number from the new number (70 - 40 = 30)

This gives us the decrease amount (30)

Step 2 - Divide

Divide the decrease amount by the new number (30 / 40 = 0.75)

This gives us the decimal number (0.75)

Step 3- Multiply

Multiply the decimal number by 100 (0.75 * 100 = 75%)

Result

The answer for our example is 75%.

Use our Percentage difference calculator to work this out for you.

Find the percentage decrease from one number to another

If something drops in number such as the amount of goods you have left, this calculation allows you to measure using percentages how much the decrease is.

As an example we will calculate what the percent decrease from 60 to 40 is.

Step 1 - Subtract

Subtract the new number from the original number (60 - 40 = 20)

This gives us the decrease amount (30)

Step 2 - Divide

Divide the decrease amount by the new number (20 / 40 = 0.5)

This gives us the decimal number (0.5)

Step 3 - Multiply

Multiply the decimal number by 100 (0.5 * 100 = 50%)

Result

The answer for our example is 50%.

Use our percentage difference calculator to work this out for you.