Your credit score is a three-digit number — typically between 300 and 850 — that lenders use to decide whether to extend credit and at what interest rate. Understanding exactly how it's calculated gives you the power to move it deliberately rather than hope it improves on its own.
The Two Major Scoring Models
The two dominant credit scoring models are FICO and VantageScore. FICO is used in over 90% of lending decisions. VantageScore is used by many free credit monitoring services. Both use the same 300–850 range and consider similar factors, but weigh them differently.
Most mortgage lenders use older FICO models (FICO 8 or FICO 2/4/5), not newer ones. If you're preparing for a home purchase, ask your lender which model they use — the strategies that move FICO 8 also move older models.
The 5 FICO Score Factors
1. Payment History (35%)
Payment history is the single most important factor. It tracks whether you've paid your bills on time across all credit accounts — credit cards, loans, mortgages, and lines of credit.
- A single 30-day late payment can drop your score 60–100 points, depending on your starting score
- The more recent the late payment, the more damage it causes
- Late payments stay on your report for 7 years, but their impact fades after 2 years
- One late payment on an otherwise spotless record is easier to recover from than a pattern
Set up autopay for at least the minimum payment on every account. You can always pay more manually — but autopay prevents the catastrophic score damage of a missed payment.
2. Credit Utilization (30%)
Credit utilization measures how much of your available revolving credit you're currently using. If your credit card limit is $10,000 and your balance is $3,000, your utilization is 30%. This factor is calculated both per-card and across all cards combined.
| Utilization Range | Score Impact |
|---|---|
| 0–1% | Maximum benefit |
| 1–10% | Excellent |
| 10–30% | Good |
| 30–50% | Negative impact starting |
| 50%+ | Significant damage |
| 75%+ | Severe damage |
Unlike late payments, utilization has no memory. Paying down your balances can raise your score in as little as one billing cycle — making it the fastest lever you have.
3. Length of Credit History (15%)
This factor considers the age of your oldest account, your newest account, and the average age of all accounts. A 10-year-old credit card is a significant asset to your score — even if you rarely use it.
Think twice before closing old credit cards. Closing a card doesn't immediately remove its history (it stays for up to 10 years), but it reduces your available credit, raising your utilization — and eventually the account will disappear entirely, lowering your average account age.
4. Credit Mix (10%)
Having different types of credit — revolving (credit cards, HELOCs) and installment (auto loans, mortgages, student loans, personal loans) — demonstrates to lenders that you can handle varied debt obligations responsibly. You don't need every type, but a healthy mix helps.
5. New Credit Inquiries (10%)
When you apply for credit, the lender performs a hard inquiry on your report. Each hard inquiry can lower your score by 5–10 points. Multiple inquiries in a short window look risky to lenders — with one exception: rate shopping for a mortgage, auto loan, or student loan within a 14–45 day window counts as a single inquiry under newer FICO models.
Score Ranges and What They Mean
| Score Range | Classification | Typical Impact |
|---|---|---|
| 800–850 | Exceptional | Best rates on all products |
| 740–799 | Very Good | Better than average rates |
| 670–739 | Good | Near or above average rates |
| 580–669 | Fair | Higher rates, some approvals |
| 300–579 | Poor | Denials or secured products only |
How Long Does It Take to Improve?
Improvement speed depends on what's holding your score down. Reducing utilization is the fastest — results visible in 30–60 days. Removing a collection or resolving a late payment dispute takes 30–90 days after the bureau updates. Recovering from a bankruptcy or foreclosure takes 2–7 years, though scores often start recovering 1–2 years after discharge.
Focus on payment history and utilization first — they account for 65% of your score. Getting these two right will produce the fastest, largest improvements.