What it means
The score is produced by a statistical model that weighs different parts of a credit file and outputs a single figure. In the most widely used consumer models the weightings are roughly 35% payment history, 30% amounts owed, 15% length of credit history, 10% new credit applications and 10% the mix of credit types held.
Payment history dominates for an obvious reason: the single best predictor of whether someone will pay next month is whether they paid last month. Amounts owed matters nearly as much, and within it credit utilisation, meaning balances as a share of available limits, is the figure most people can move fastest.
The practical effect of a score is financial rather than reputational. A borrower moving from a fair score to an excellent one might see a mortgage rate fall by well over a percentage point, which on a large long-dated loan translates into tens of thousands of dollars of interest across the term.
Business credit scores work on the same principle but use different scales and inputs, often running from 1 to 100 and drawing heavily on supplier payment data, industry risk and company filings. Small business owners frequently find that both their personal and business scores are assessed when a personal guarantee is involved.
The most common misunderstanding is that there is one universal score. In reality there are many models from several agencies, all reading slightly different data, so the number a consumer sees on a free app is rarely the exact figure a lender uses.
The direction of travel matters far more than the precise digit.
In practice
Real-world examples.
Example
A couple applying for a $350,000 mortgage delay their application by four months to pay down two credit cards. Their score rises enough to move them into a better rate band, cutting their monthly payment by roughly $140.
Example
A car dealership's finance desk quotes three tiers of interest rate keyed directly to score bands. A customer 12 points below a threshold accepts a slightly smaller loan to reduce the amount financed and qualifies for the cheaper tier.
Example
A small manufacturer is asked for a personal guarantee on a $250,000 facility, so the lender pulls the director's personal score alongside the company's business score. A recent missed payment on the director's card leads to a higher rate on the company loan.
Think of it
“Credit score is your creditworthiness number-determines what rates you get.
Formula
Calculation
Scores come from proprietary models, but the weighting logic can be shown as: weighted rating = sum of (each category rating x its weight), then mapped onto the score range as: score = 300 + (weighted rating / 100) x 550
Take a borrower rated out of 100 in each category: payment history 95, amounts owed 60, length of history 80, new credit 70 and credit mix 75. Applying the standard weightings gives (95 x 0.35) + (60 x 0.30) + (80 x 0.15) + (70 x 0.10) + (75 x 0.10).
That works out as 33.25 + 18.00 + 12.00 + 7.00 + 7.50 = 77.75 out of 100. Mapping onto a 300 to 850 range gives 300 + (77.75 / 100 x 550) = 300 + 427.6 = 728 after rounding.
The weakest input is amounts owed at 60, driven by carrying $6,000 of balances against $20,000 of limits, a utilisation of $6,000 / $20,000 = 30%. Paying the balances down to $2,000 takes utilisation to 10% and might lift that category rating to 90, which would raise the weighted rating by (90 - 60) x 0.30 = 9 points and the mapped score by 9 / 100 x 550 = about 50 points.Case study
Seen in the real world.
This is an illustrative and clearly fictional example. Marisa Kelling, an invented cafe owner used here to demonstrate the mechanics, wanted to finance a second site and was quoted 11.9% on a $180,000 loan, well above what she had expected given nine years of profitable trading.
The lender's explanation pointed at her personal score of 648, which was dragged down by two credit cards sitting at 92% of their limits. She had never missed a payment, but utilisation alone was doing the damage. In this fictional scenario she spent seven months clearing the balances to under 15% of limits and opened no new accounts in the meantime.
Her score recovered to 741 and the lender reissued the offer at 8.4%. On a $180,000 five year loan the difference amounted to roughly $17,000 of interest, earned entirely by moving money she already had into the right accounts before applying.
Watch out
Common mistakes.
- Believing that carrying a balance on a credit card builds a better score, when paying in full each month reports the same on-time history with lower utilisation.
- Applying to several lenders in quick succession while rate shopping, which can stack up hard searches and dent the score.
- Treating the free score shown by an app as the definitive figure, when lenders use different models that can produce a materially different number.
Questions
People also ask.
How quickly can a credit score improve?
Utilisation changes can show within one or two billing cycles, while the effect of missed payments or defaults fades over years rather than months.
Does income affect a credit score?
No, income is not part of the score itself, though lenders consider it separately when deciding affordability.
What counts as a good score?
On a 300 to 850 scale, roughly 670 and above is usually treated as good and 740 and above as very good, though every lender sets its own thresholds.
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