Current Balance: Enter your credit card balance today. If you want your exact credit card balance, you will probably have to call the customer service number on the card: if you carry a balance, it almost always increases from day to day.
Interest Rate: Enter the APR of the credit card as a percentage.
Current Monthly Payment: The amount per month you are paying toward your credit card balance now. Do not enter the minimum monthly payment unless that's all you are paying.
New Monthly Payment: The monthly payment you will make in the future.
New Charges/Month: The total amount of new charges you make to your card on average each month.
Major Purchase: If you are considering making a large purchase using your credit card, enter the amount of that purchase. If you do not expect to make a major purchase, ignore this field.
Months From Now: If you entered a major purchase above, enter the number of months from today that you will make that purchase. If you are making that purchase in this billing period, enter "0." If you are not going to make a major purchase, you can ignore this field.
Credit Cards, Credit Card Interest, and Credit Debt Explained
Credit cards are easily the most expensive kind of financing the average person will every take out. Short of taking out a short-term payday loan or going to a loan shark, you are unlikely to do worse.
The Time Value of Money and Interest
Time may not be money but it does make money. If you carry a credit card balance, time is making money off you for the benefit of the credit card issuer. With every day that you carry a balance, you are paying interest not only on your purchases, but on the interest owed on past balances. This means that credit card interest does not just grow at a steady rate; rather, it accelerates. A hundred-dollar balance now will add more and more interest until it's twice that, if all you make is the minimum payment.
Conversely, the more you pay toward your balance each month, the less you'll owe in the future. It's much, much, better to make a payment toward your credit card balance today than tomorrow. That hundred dollars today will simply be worth much more than a hundred dollars a day or a month from now. Why? Because the hundred dollars today will save you interest on that part of your balance you've paid off.
Credit Card Penalty Fees
After interest, credit card issuers rake in the second largest amount of money from penalty fees. Usually, penalty fees are for making a payment late or going over the credit limit, which do cause trouble for the credit card issuing companies. But in reality, most consumer advocates believe that the credit card companies make much more off the penalty fees than they lose on cardholders' mistakes. The calculator does not take penalty fees into account, but they're a good reason to get credit card balances off your back.
Minimum Monthly Payment
Credit cards usually demand a "minimum monthly payment." What you have to remember is that this minimum monthly payment really is a very bare, low minimum. If you only pay the minimum every month, you will be up to your eyeballs in debt for quite a long time.