ThomasGoodwin.com

Finally, a calculator that goes beyond just computing monthly payments!

I’ve tried a few of the other online mortgage and installment loan calculators, e.g. Yahoo! Finance has a decent one, but none of them that I’ve found have a place where you can find out what kind of impact adding additional principal payments will do to paying off your loan early.

So I created the following calculator in Microsoft Excel that you can easily use to compute the monthly payments on anything with a regular installment loan, whether it’s a mortgage, car, boat or similar amortized loan.

You can enter information in any field labeled with green. You will notice there’s a column entitled “Additional” in the amortization schedule. This is where my spreadsheet is different from the online calculators that just show you monthly principal and interest! Any amount that you type into this “Additional” column will show you the impact of paying down your loan faster. Whether it’s adding $50 to each month, or making one extra payment in the 1st, 12th, or 24th month, etc. you will instantly see the difference that it will make in how quickly your loan gets paid off.

When you add in additional principal payments you will notice that the loan balance will go to zero or even negative sometime before the last scheduled payment. The month that the loan goes to zero or negative is the point where it will be paid off! Leaving the “Additional” column empty will cause it to take exactly the number of periods to pay off the loan that you took out, so a 30 year mortgage would take all 360 months but adding in one extra principal payment in the 12th month and suddenly you knocked the last 7 years or so off of the loan!

I added in a Second Mortgage field and amortization schedule but this could just as easily be used to compare two loans side-by-side or to compare the effects to paying differing amounts of additional principal on your loan.

Give it a try! Without further ado, here is the spreadsheet in Microsoft Excel! If you are prompted to put in “Authentication” Information such as user name and password just hit the cancel button next to the user name and password fields and it will then download the spreadsheet. I don’t know why it’s asking for that! I don’t have the document password protected! You may also want to right-click on the link and select “Open in New Window”. I apologize for any technical difficulties!

As always, I appreciate your comments and feedback!

This entry was posted on Sunday, February 8th, 2009 at 3:15 pm and is filed under Consumer Credit Issues, Mortgage News, Real Estate. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.