Add or Subtract Percentage Calculator
You can use this calculator to add percent to a number, or to subtract percent from it, to get the final amount.
Total amount = 120
Lets assume the total amount is N.
Formula given, N = Amount + Percent to add/ × | Amount |
So, N = 100 + 20/ × | 100 |
Or, N = 100 + ( 0.2 × 100 )
Or, N = 100 + 20
So, N = 120
Final amount = 80
Lets assume the final amount is N.
Formula given, N = Amount - Percent to subtract/ × | Amount |
So, N = 100 - 20/ × | 100 |
Or, N = 100 - ( 0.2 × 100 )
Or, N = 100 - 20
So, N = 80
Formula to add percent to a number
Total Amount = Amount + Percent to add/ × | Amount |
Formula to subtract percent from a number
Final Amount = Amount - Percent to add/ × | Amount |
I have added the absolute sign at the last amount value in the formula, because without that, the answers would be wrong if amount is in negative. For example, when you add 20% to -100, without converting the last amount value to positive, you get -120 which is incorrect.
How to use this calculator?
Just add the amount and the percent of the amount to add or subtract in the relevant box. After you click on calculate, it will show you the formatted answer (rounded off to 4 decimal places) at the top of calculator form, and the calculation steps below the form.