Even if you've spent hours scrutinizing every item on your credit report, you still may not know if you've got a good credit record or a bad one.

A

recent column explained how to retrieve your credit report from one of the three big credit-reporting agencies --

Equifax,

Experian and

Trans Union. You should check your credit report for inaccuracies that could seriously damage your chances of buying a home or car, renting an apartment or even getting a job.

But a credit check won't get you any closer to understanding your credit score. This score may be unfamiliar to everyday people, but it looms large for the lenders that are deciding whether to let you buy that house or other item.

Your credit score is a triple-digit number that tells a lender how likely you are to pay back a loan. Essentially, it compresses your entire credit report into a single number, ranging from 300 to 900. Generally, you need a 620 or better to get a loan or a mortgage from an established lender.

You may be wondering how you can get your hands on your score. It's not so easy, but, thankfully, that may be changing.

Fair, Isaac & Co.

, the masterminds behind the FICO credit score used in making more than 75% of new mortgages every year, is creating a Web-based service that will explain individual scores to consumers. By the end of the year, Trans Union will start providing a rating that approximates your credit score when you order a copy of your credit report. You may also be able to get the number by asking your lender.

In the meantime, Fair Isaac provides some guidance. The San Rafael, Calif., company has listed on its

Web site the five factors used in calculating your score.

Payment History

Obviously, paying your bills on time is of paramount importance. Accordingly, payment history constitutes about 35% of your credit score.

The FICO score considers payment information on all your credit cards, accounts at department stores, mortgages and car loans. Certainly, bankruptcies, liens and collection items would show up here and are more damaging to your credit than a few late credit-card payments.

The score takes into account late or missed payments. As a rule, a 30-day late payment isn't as detrimental as a 90-day late payment. But how recent and how regular your late payments are also factors in. A 90-day late payment from several years back will count less than a 30-day late payment from a few months ago.

Canceling a card or closing an account doesn't erase a late payment from your record or score.

Basically, a good payment history on most of your accounts will raise your score. And one or two late payments won't destroy your score if you have a good credit history.

Amounts Owed

Next, you should be concerned about how much you owe; it makes up 30% of your FICO score. Lenders are trying to figure out if you owe too much money for your station in life and if you'll have trouble making payments in the future.

A large number of accounts that carry balances can show that you're overextended. Using up most of your total credit line by maxing out many of your credit cards will hurt your score, because you look like you might have difficulty making payments down the road.

Even if you pay off your cards every month, your credit report might still show a balance. The total balance on the most recent statement is the amount that shows up on your credit report.

Closing an unused account that doesn't have a balance won't really help your score.

Length of Credit History

Your credit score also includes the length of your credit history, which comprises 15% of the tally. Generally, a longer history will improve your score, but you can still have a good record with a short history.

You need to have some credit history to have a credit score. Sometimes having a very limited credit record can have a negative effect.

New Credit

This category makes up 10% of your score.

The big issue here is how much new credit you've taken on recently. You want to avoid opening several new credit cards or accounts in a short span of time. In credit scoring, you look like a bigger risk if you do.

This factor also applies to how many recent requests you have made for credit, which is shown by inquiries to credit reporting agencies. (Inquiries for credit-card promotions or ones that you've made just to check your report don't count against you.) If you're trying to obtain several new lines of credit, you look like a bigger risk.

Types of Credit in Use

Your mix of credit cards and accounts is the basis for 10% of your score. According to Fair Isaac, credit mix typically isn't a major factor in determining your score, but it will be important if your credit report doesn't have a lot of other information on which to base a score.

How many accounts is too many? It varies for different credit profiles. But, basically, it's not a hot idea to open credit accounts that you don't intend to use, according to Fair Isaac.

Simply, if you pay your bills on time and borrow money in moderation, your credit score and profile should look pretty healthy. If you have too many credit cards and have trouble paying your bills when they're due, you probably need to clean up your record and improve your habits.

Either that, or turn over your finances to your spouse.

Send your questions and comments to

deardagen@thestreet.com, and please include your full name.

Dear Dagen aims to provide general fund information. Under no circumstances does the information in this column represent a recommendation to buy or sell funds or other securities.