Summarize:

When calculating your income for you debt-to-income ratio, use the amount of money you make before taxes and not what you make after taxes are taken out. Example: If the person in the example continued from above makes $39,000 on a yearly basis before taxes, or $750 a week before taxes, one of these figures should be used instead of a net income figure. Divide your annual gross income by 12 to determine your average monthly income.  If you do not know your annual gross income, take your weekly income and multiply it by the number of payments you receive in a year. If you get paid every other week, this would be 26 payments; for payment that occurs weekly, this would be 52 payments. This will give you your annual income, and you can divide this number by 12 to determine your monthly income. Alternatively, you can take your weekly payment and multiply it by 4.3 or multiply your bi-weekly pay by 2.15 to determine your rough monthly income. Example: If a person's yearly gross income is $39,000, then: 39000 / 12 = $3250  If a person's weekly gross income is $750, then: 750 * 52 = 39000; 39000 / 12 = $3250 Alternatively, if a person's weekly gross income is $750, then: 750 * 4.3 = $3225 If you received commissions, bonuses, tips, overtime, or money from other sources, like alimony, rental income, investment income, pension, disability, or child support, add that money to your monthly income. Example: If you receive investment income of roughly $200 each month, add that to your monthly gross income of $3250, giving you a total income of $3450.
Use your gross income figures. Determine your monthly income. Add in any other regular payments you receive.