What factors actually determine my credit score?

The five factors and what they weigh

FICO's standard scoring model uses five factors. The percentages are approximate — the exact weights vary slightly depending on the version of the model and the specifics of your file — but they hold up well as a guide to what matters:

1. Payment history — 35%
2. Credit utilization — 30%
3. Length of credit history — 15%
4. Credit mix — 10%
5. New credit — 10%

Two factors do most of the work. Payment history and utilization together make up 65% of the score. The other three add nuance but rarely swing the score the way the first two can.

Payment history (35%)

The single biggest factor. Whether you've paid your accounts on time, and how recently any missed payments occurred. Late payments, collections, charge-offs, bankruptcies, foreclosures, and judgments all sit in this bucket.

Newer negative items hurt more than older ones. A 30-day late mark from last month carries more weight than a 30-day late mark from four years ago. A late payment that's incorrectly reported is the single most common item worth disputing, because correcting one inaccurate late mark can move a score meaningfully.

Credit utilization (30%)

How much of your available credit you're currently using. Calculated as your total revolving balances divided by your total revolving limits. A $1,000 balance on a $5,000 limit is 20% utilization.

Lower is better. Conventional wisdom says keep utilization under 30%; the lowest-rate scoring usually shows up below 10%. Utilization is calculated both per-card and across all your cards, so a single card maxed out can hurt even if your overall utilization looks fine.

Utilization is the one factor that can change quickly. Paying down a balance shows up on your report within a billing cycle and can move your score fast. Inaccurate balances reported by lenders — a balance that should be $0 still showing as $4,200 — are also high-value items to dispute.

Length of credit history (15%)

How long your accounts have been open. Includes the average age of all your accounts, the age of your oldest account, and the age of your newest account.

Older is better. This is the factor that's hardest to change in the short term because it depends on time. It's also why closing your oldest credit card is usually a bad idea — losing that account immediately reduces your average account age.

Items that affect this factor and are worth disputing: accounts incorrectly reported as closed when they're still open, accounts with the wrong "date opened," and accounts that have aged off your report but are still listed.

Credit mix (10%)

The variety of credit types in your file. Revolving credit (credit cards), installment loans (auto, personal, student), mortgages, and retail accounts all count. Having a few different types tends to help; having only one type tends to be neutral or slightly negative.

This is a small factor and not worth optimizing for in isolation. Don't open accounts you don't need just to improve your mix.

New credit (10%)

Recent credit activity. Hard inquiries from credit applications, recently opened accounts, and the rate at which you're applying for credit. Multiple applications in a short window — especially for credit cards — can drag this factor down.

Hard inquiries fade in importance after a few months and fall off your report after two years. Unauthorized hard pulls are disputable.

What this means for dispute work

Knowing which factors carry the most weight tells you where errors hurt the most:

• An inaccurate late payment hits the 35% factor — usually the biggest move when corrected
• An incorrect balance or closed account still reporting a balance hits the 30% factor
• An account with the wrong "date opened" or one that should have aged off hits the 15% factor
• An unauthorized hard inquiry hits the 10% factor

CreditRefresh's AI scans for items in all of these buckets and drafts dispute letters for the ones with grounds. The biggest score movements tend to come from corrections to payment history and utilization, which is where the AI tends to focus first when it finds disputable items.

What doesn't go into your score

A few things that aren't part of the standard FICO formula but get talked about as if they are:

• Income. Lenders look at income separately when deciding whether to extend credit, but it isn't in the score.
• Employment. Same as income — relevant to applications, not to the score.
• Race, age, gender, marital status, ZIP code. These are excluded by federal law from credit scoring.
• Soft inquiries. Don't count. Don't appear to lenders.

Understanding the formula doesn't make the score easy to game. It does make it easier to recognize what's actually moving the number and what isn't.