All About Credit
Credit Usage Ratio is the amount of your debt versus your credit limit. For instance a 1,000 limit credit card with a balance of $300 has a 30% credit usage ratio. The same $1,000 limit credit card with a $900 balance has a 90% credit usage ratio. If you want to score high in this section you will need to keep your balances on your credit cards below 30% of their credit limit. The closer you get to your credit limits, the more points will be subtracted from your score. The bottom line: keep your balances at 30% or less of your credit limits.
This section accounts for 30% of your score.