What this calculator does
Credit utilisation is the share of your available credit that is currently in use, and it is one of the larger inputs into most credit scoring models. The common guidance is to keep it below 30 per cent, with below 10 per cent better still.
What surprises people is that it is usually measured on the statement balance, not on what remains after you pay. Paying in full every month does not guarantee low reported utilisation if the balance is high on the day the statement closes.
The formula
Each card's balance is divided by its limit for the per-card figure. Overall utilisation divides total balances by total limits, which is the figure scoring models weigh most heavily.
| Term | Meaning |
|---|---|
| Utilisation | Balance divided by credit limit, as a percentage. |
| Overall utilisation | Total balances across all cards divided by total limits. |
| Per-card utilisation | The same figure for an individual card, which some models also consider. |
The inputs explained
| Field | What to enter |
|---|---|
| Balances (comma separated, one per card) | Current balance on each card, comma separated. |
| Credit limits (comma separated, same order) | The credit limit on each card, in the same order as the balances. |
When to use it
Preparing to apply for a loan
Lowering utilisation before an application can improve the score a lender sees.
Deciding which card to pay down
A single card near its limit can weigh on a score even when overall utilisation is fine.
Assessing whether to close a card
Closing an unused card removes its limit from the total, which raises utilisation.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
What do different balance levels look like?
The same $15,000 of total credit at three levels of use.
| Balances | Overall utilization | Total balance |
|---|---|---|
| $2,500 total | 16.7% | $2,500.00 |
| $5,000 total | 33.3% | $5,000.00 |
| $10,000 total | 66.7% | $10,000.00 |
Questions
Why is 30 per cent the usual ceiling?
It is a rule of thumb rather than a hard threshold in any model. Scores generally decline gradually as utilisation rises, with no cliff at 30, but the guidance is a reasonable simplification of that curve.
Does paying in full each month give zero utilisation?
Not necessarily. Most issuers report the statement balance, so whatever was owing on the statement date is what gets reported, even if you pay it off in full days later.
Should I close cards I do not use?
Doing so removes that card's limit from your total available credit, which raises utilisation on the same balances. It can also shorten your average account age. There are reasons to close a card, but improving utilisation is not one of them.
Does per-card utilisation matter separately?
Some scoring models consider it alongside the overall figure, so one card sitting near its limit can be a mild negative even when the total looks healthy. Spreading balances can help marginally.
For comparing payoff strategies across several debts, see the debt payoff strategy calculator. For whether moving a balance is worthwhile, see the balance transfer calculator.