This doesn't deal with inflation, taxes or any of that complicated stuff. This is just a simple calculator that lets you start with an amount of money and make regular monthly deposits, and see how much it grows.

This calculator allows you to show a full amortization schedule after you input the Principal, Interest Rate, Term, starting month, and year. It also allows you to model a variety of prepayment options, such as monthly or lump sum, and summarizes the savings.

This form allows you to compare what would happen if you took one of two choices with some extra cash you have -- prepaying your mortgage each month, or investing it instead. This tries to take into account your tax situation and assumes you always itemize (even late into your mortgage when the interest portion of your monthly payment is less -- I am assuming you give to charities, and pay state and local taxes too!!)

This calculator finds the missing variable for a loan. If you know the payment, term and the loan amount it calculates the interest rate. If you know the payment amount, loan amount and the interest rate, it calculates the term. Get the idea? Just make sure to leave one box (and only one box) empty.

This form allows you to compare what would happen if you took one of two choices with a big chunk of cash you have -- paying off your mortgage, or investing it instead. This tries to take into account your tax situation and assumes you always itemize (even late into your mortgage when the interest portion of your monthly payment is less -- I am assuming you give to charities, and pay state and local taxes too!!)

To determine if you should invest or prepay your mortgage, you need to compare cost of borrowing with the potential return from investing. If your cost of borrowing is a 6% net after tax interest rate, and you can invest assuming an 8% after-tax rate, it may be better to invest since the money may generate 2% more than you by reducing the debt burden of 6%

I am assuming you give to charities, and pay state and local taxes too!!)

This form allows you to see how prepaying your mortgage reduces the length of your mortgage by putting in the current values for your loan. If you know your current principal balance and principal/interest payment, enter then in fields A1 and A2. Otherwise enter the three values for your loan in B1, B2 and B3. (Original Loan Amount, Month of First Payment, Length of Loan).

This calculator takes a principal amount, interest rate, normal length of the loan, and then allows you to determine how long you’d like the loan to last (in which case it will solve for your new payment to meet that remaining term, or how much you’d like to pay (in which case it will solve for your new remaining term based on that new payment).

NEW: Now also calculates for credit cards and other non amortized lines of credit that use simple compounding of interest.

Enter the values below. The calculator will work to calculate what kind of income needed to qualify for specific values. Enter in the monthly payment, taxes, home owners insurance, other debt payments, sale price of home and expected down payment, and the calculator will give you an estimate of how much income you will probably need to qualify.

Use this to compare the real after-tax interest rate of your mortgage. Then compare your after-tax yields on taxed investments and tax protected (i.e. tax-deferred 401(k),403(b),IRA accounts or tax free Roth or Education IRA accounts).

The calculator will work to calculate what kind of income is needed to qualify for specific values. Enter in the monthly payment, taxes, homeowners insurance, other debt payments, the sale price of the home and expected down payment, to estimate the income needed.

Use this to compare the real after-tax interest rate of two different rates. Compare the cost of one interest rate versus the return of another investment after tax. This can be helpful to analyze your LAG - Liability Asset Gap between a loan and an investment.

The calculator will take multiple loan balances and multiple interest rates and calculate the overall cost of all your debt. A great way to see how larger debts or smaller debts with higher interest rates skew the overall cost of your borrowing