Credit Utilization Calculator Formula

Understand the math behind the credit utilization calculator. Each variable explained with a worked example.

Use the Credit Utilization Calculator

Formulas Used

Credit Utilization

utilization = total_limits > 0 ? total_balances / total_limits * 100 : 0

Ideal Balance (Under 30%)

ideal_balance = total_limits * 0.30

Excellent Balance (Under 10%)

excellent_balance = total_limits * 0.10

Pay Down to Reach 30%

amount_to_paydown = max(total_balances - total_limits * 0.30, 0)

Variables

VariableDescriptionDefault
total_balancesTotal Credit Card Balances(USD)3000
total_limitsTotal Credit Limits(USD)15000

How It Works

Credit Utilization Ratio

Utilization = Total Balances / Total Credit Limits x 100%

This is one of the most important factors in your credit score, accounting for about 30% of your FICO score.

Utilization Thresholds

| Utilization | Impact | |---|---| | 0-10% | Excellent | | 10-30% | Good | | 30-50% | Fair | | 50-75% | Poor | | 75-100% | Very Poor |

Worked Example

$3,000 balances across cards with $15,000 total limit.

total_balances = 3000total_limits = 15000
  1. 01Utilization = $3,000 / $15,000 x 100% = 20%
  2. 02This is in the "Good" range (10-30%)
  3. 03Ideal balance (30%) = $4,500
  4. 04Excellent balance (10%) = $1,500

Ready to run the numbers?

Open Credit Utilization Calculator