How 401(k) Plans Work


Taxed and Non-taxed Compounding Calc

Taxed and Non-taxed Compounding Calculator


Taxes can have a big effect on the amount of money that accumulates in an account, especially when money is left in an account for a long period of time. In a tax-sheltered account (for example, an IRA account), you do not have to pay taxes on interest until you actually withdraw the inter est from the account. Therefore, you can earn interest on all of the interest you earn. In a normal account (a savings account, CD, etc.), you pay taxes on the interest each year, so you earn less.

This calculator shows you how much money you can make by leaving a sum of money in an account at a certain interest rate. It helps you to understand the difference that tax-sheltered compounding can make, and also shows you the effect of inflation. Enter the amount of money that you wish to deposit initially, the expected interest rate, and the expected inflation rate. The calculator will show you the amount that will accumulate in the account over different time spans both with and without taxes. It will also show you how much money that initial amount will buy in the future because of inflation -- that way, you can see if an investment actually grows (beats inflation).

Amount to deposit
Enter the amount of money that you will initially deposit in the account.
Interest rate
Enter the interest rate. If you wish to use a 5.0% interest rate, enter 5.0. As of March 1, 2002, here are some typical rates: passbook savings account: 1% - 3%; one year CD: 2% - 3%; stock market average return: 10.5%.
Federal and state tax rate
Enter the sum of your federal and state tax rates. For example, if you are in the 23% federal tax bracket and your state has a 7% income tax rate, enter 30 here. If you have no idea, use 30.
Inflation rate
Enter the expected inflation rate over the period of time. If you have no idea, try 4% (enter 4).
Click this button to calculate the account value.
Year Value: Tax-free compounding Value: Taxed compounding Inflation
After 1 year
After 2 years
After 3 years
After 4 years
After 5 years
After 10 years
After 15 years
After 20 years
After 30 years
After 40 years

It is particularly interesting to note the massive difference between the taxed and non-taxed numbers after 20 or 30 years. There are several ways to save money that make use of completely tax-free compounding:

  1. In a 401(k) account
  2. In an IRA account
  3. By purchasing individual growth stocks that do not pay dividends or that reinvest dividends
  4. By using certain types of annuities or life insurance

The inflation column shows you the effect of inflation on your initial deposit. For example, if you deposit $1,000 in an account and the inflation rate is 4%, then the value in the inflation column will be $1,040 after one year. This means that in one year it will take $1,040 to buy what costs you $1,000 to buy today. If your investments do not at least exceed the rate of inflation, you are losing money. If you look at the account value and it is less than the value in the inflation column over time, then your investment is actually losing money. Taxes often have that effect on lower-performing investments like savings accounts and CDs.


Calculators courtesy of BYG Publishing, Inc.