Lender will calculate your DTI ( Debt to Income ratio). If your total debts ( new home PITI + credit card loan if any + car loan + any loans you might have) monthly / incomes before tax < 45%, you will be OK.
The minimum payment on credit card debt is calculated as a percentage of your total current balance, or as all interest plus 1 percent of the principal. monthly gross salary是税前的,什么都没扣的.