Most consumers understand that a good credit score is vital to one's financial security and stability. Many people may not understand how a credit score is calculated. Payment history accounts for roughly 35% of one's overall score. This means that on-time payments are absolutely essential. Debt level is not far behind at 30%. This accounts for near-limits and the total amount of money owed. Length of credit history is next at 15%, followed by inquiries at 10% and mix of credit at 10%.