Credit utilization calculator (debt-to-credit ratio)

For each card with a limit greater than zero the calculator works out utilization = balance ÷ limit × 100, rounded half-up to one decimal place. The overall ratio is Σ balance ÷ Σ limit × 100 over the same cards; a card whose limit is blank or zero is excluded from both totals and reported as left out. A balance above the limit gives a ratio over 100% and a warning.

The band is read from the displayed overall ratio: under 10% excellent, under 30% good, under 50% fair, under 75% high, and 75% or more very high. These are a general guide used for labelling, not a scoring rule.

The pay-to-target figures use the target T you chose: overall max(0, Σ balance − T × Σ limit), and per card max(0, balance − T × limit). Both are rounded up to the smallest unit of the currency so that the target is actually reached rather than missed by a cent. The limit increase that would do the same job without a payment is max(0, Σ balance ÷ T − Σ limit), also rounded up.

When you enter a planned payment the calculator allocates it by water-filling. It takes the card or cards with the highest ratio and pays them down until they match the next-highest card; then it pays that larger group down together, in proportion to their limits, until they meet the next level, and so on until the payment is spent. If every remaining card is at the same ratio, the payment keeps lowering all of them pro-rata by limit. Amounts are rounded half-up to the smallest unit, with any rounding remainder going to the card with the highest ratio. A payment larger than the total owed clears every card and the surplus is reported separately. The allocation minimises the highest per-card ratio; it takes no account of interest rates, so a card with a high APR is not favoured. The credit card payoff calculator looks at the cost side.

Full method, rounding and tests on the methodology page

There is no single published cut-off, and the scoring models do not publish their weightings in detail, but the guidance from bureaus and regulators is consistent in direction.

United States and Canada. Experian describes 30% as the point at which utilization starts to have a more pronounced negative effect on a score and suggests that keeping the rate around 10% is better still; the Consumer Financial Protection Bureau’s guidance on keeping a good score says experts advise using no more than 30% of your total credit limit, and notes that scoring models look at how close you are to being “maxed out”. Experian also says utilization could affect around 20% to 30% of a credit score, depending on the scoring model. Canadian bureau guides describe the same mechanics.

United Kingdom. Experian UK’s guide puts the rule of thumb at 25%: “try to keep your credit utilisation below 25%”. UK scores are built from similar data, and lenders also see the limit and balance on each account when they assess an application.

Australia, New Zealand and Ireland. These countries use comprehensive credit reporting, in which lenders report account details and repayment history rather than relying on a utilization-style figure. Australian credit reports include repayment history and defaults, as the Office of the Australian Information Commissioner explains; in Ireland the Central Credit Register, run by the Central Bank of Ireland, stores personal and credit data for loans over 500 euro. The ratio is still useful there for seeing how much of your available credit you use, and some lenders look at card limits when they assess affordability, but the band labels on this page are drawn from the US and UK guides and should be read loosely elsewhere.

Whatever the country, the ratio is calculated from what is on your credit report, which is normally the balance the issuer reported on the statement date rather than the balance today. A payment made after the statement closes shows up in the next report. Our guide to how credit card interest works explains statement dates and grace periods.

Both are reported. The overall ratio is the one most guides quote, and it is the figure the headline shows. Scoring models also look at individual accounts, which is why the per-card table matters: in the worked example the overall ratio is a comfortable 22.2% while one card sits at 40%. That is also why a planned payment is worth splitting rather than paying wherever is convenient, and it is why a card at or over its limit is flagged even when the overall figure looks fine.

Cards with no limit are a common snag. Some charge cards and some store cards have no fixed limit, and some issuers report a “high balance” instead of a limit. The calculator leaves such a card out of every ratio and says so, rather than dividing by zero or guessing. If you know the limit the issuer actually reports, enter that.

Utilization is only one of the ratios lenders look at. The debt-to-income ratio calculator compares your monthly payments with your income, which is the figure mortgage lenders weigh most heavily; our guide to the debt-to-income ratio explains how the two differ. And because utilization ignores interest, the credit card payoff calculator is the place to see what a card balance costs over time and how long a payment takes to clear it.

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• CFPB — How do I get and keep a good credit score?
• Experian (US) — What is a credit utilization rate?
• Experian (US) — Proportion of balances to high credit on revolving accounts
• Experian (UK) — What is a credit utilisation ratio?
• Office of the Australian Information Commissioner — Credit reporting
• Central Credit Register (Central Bank of Ireland) — Apply for your credit report and other rights

Estimates for general information only — not financial, credit or legal advice. Your actual figures depend on your lender’s or card issuer’s exact terms, fees, minimum-payment rules, interest calculation method and any changes they make. Check your statements and speak to a qualified adviser before making decisions. Scoring models weigh utilisation in their own ways and use the balances and limits reported to the bureaus, which may differ from today’s; the bands here are a general guide, not a score prediction.

Page reviewed October 9, 2026 by the DebtWren team · Methodology · Changelog · Report an error