# Calculate Percentage ## Calculate Percentage

Enter two numbers and this calculator will compute what percent of the second number the first number represents to one thousandth of a percent.

 is what % of

## Calculate Number Associated With a %

Enter a percent and a starting number and this calculator will figure the number associated with that percent of the initial number accurate to a thousandth.

 What is % of

## Calculate Percent Change

Enter the starting number and the final number to computer what percent the first number changed to become the second number. This is useful for tracking price discounts, investment growth, or other things that change over time.

 starting number final number percent change

Here are instructions for the formulas to calculate common percent related math problems:

• percentage
• formula: (x/y) * 100 = z%
• in words: divide x by y to get its decimal number & then multiply by 100 to convert the decimal into a percent
• number associated with a percentage
• formula z% / 100 * x = y
• in words: divide the desired resultant percent by 100 to convert it to a decimal, then multiply it by the original number to solve for the number which is associated with that percent of the original number
• percent change
• formula: (y-x)*100/x = z% change
• in words: subtract the original number from the final number, multiply this result by 100 (move the decimal 2 places to the right) and then divide this value by the original number to get percent change 