What a Credit Score Is
A credit score is a three-digit number, usually 300 to 850, that predicts how likely you are to pay debt back as agreed. Lenders use it to make faster, steadier decisions about who to lend to and at what rate. Higher score, lower predicted default risk, better terms, lower rates, higher approval odds. That is the whole game.
The dominant scoring model is FICO, built by Fair Isaac Corporation. FICO scores show up in about 90% of significant lending decisions in the U.S. VantageScore, built by the three major credit bureaus together, mostly shows up in free credit monitoring tools and some specific lending contexts.
Your credit score is built from your credit report, which is kept by three credit bureaus: Experian, Equifax, and TransUnion. Each bureau may have slightly different data because not every lender reports to all three. That is why your score can drift a little across the three.
The Five Factors in Your FICO Score
Payment history (35%): Do you pay your bills on time? A single payment that is 30 or more days late can knock a good score down 60 to 100 points. This is the heaviest factor by a wide margin.
Credit utilization (30%): How much of your available revolving credit you are using right now. Using $3,000 of a $10,000 total limit is 30% utilization. Lower is better. Most scoring models reward utilization below 30%, and well below 10% for the best scoring.
Length of credit history (15%): How long your accounts have been open, including the age of your oldest account, your newest account, and the average age across all of them. Old accounts in good standing are worth keeping, which is why closing them, even when unused, often hurts more than it helps.
Credit mix (10%): Having a mix of revolving (credit cards, lines of credit) and installment (mortgages, auto loans, personal loans) accounts helps. Lenders like to see you can handle both flavors.
New credit (10%): Recent applications for new credit. Each hard inquiry can drop your score 3 to 5 points and stays on your report for two years (though the scoring impact drops after 12 months). Multiple inquiries in a short window for auto or mortgage shopping are usually treated as one inquiry by most scoring models.
What the Score Ranges Mean
300 to 579 (Poor): Most mainstream lenders decline in this range. Options narrow to secured cards and subprime products.
580 to 669 (Fair): Some lenders will approve, with higher rates and lower limits. FHA mortgages are reachable at the low end.
670 to 739 (Good): Access to most standard credit products at competitive, not top-tier, rates.
740 to 799 (Very Good): Access to most products at strong rates. Most conventional mortgages and premium credit cards open up here.
800 to 850 (Exceptional): Best available rates on everything. Lenders fight for you in this range.
How to Improve Your Credit Score
The biggest moves are paying every bill on time (turn on autopay for at least the minimums so a missed payment cannot sneak through) and knocking down revolving credit card balances to drop your utilization ratio. Those two factors together are 65% of your FICO score, and they respond to change faster than the others.
Disputing wrong information on your credit report can produce big score gains if errors exist. Pull free credit reports from all three bureaus at AnnualCreditReport.com and dispute the bad items with each bureau directly. Common errors: accounts that are not yours, late payments that were not actually late, and old negative items that should have aged off.
Avoid new credit applications when you are getting ready to apply for a mortgage or major loan. Holding off keeps your score where it is and keeps unnecessary hard inquiries out of the way.